Update 2022-03-02 15:47

2022-03-02 15:47:54 +01:00 · 2022-03-02 15:47:54 +01:00 · 21bf9fdba5
parent ac1e628013
commit 21bf9fdba5
194 changed files with 1653 additions and 1216 deletions
--- a/build/a.html
+++ b/build/a.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1645,7 +1645,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/a_l.html
+++ b/build/a_l.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1728,7 +1728,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/c.html
+++ b/build/c.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1645,7 +1645,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/c_m.html
+++ b/build/c_m.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1651,7 +1651,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/c_m_cs.html
+++ b/build/c_m_cs.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1647,7 +1647,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/c_m_cs_cyl.html
+++ b/build/c_m_cs_cyl.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1667,14 +1667,14 @@ Range of parameters:  \(r \in [0, \infty[\), \(\varphi \in [0, 2\pi[\) and \(z \
 <div id="outline-container-c_m_cs_cyl_grad" class="outline-6">
 <h6 id="c_m_cs_cyl_grad"><a href="#c_m_cs_cyl_grad">Gradient</a></h6>
 <div class="outline-text-6" id="text-c_m_cs_cyl_grad">
-<div class="eqlabel" id="org5cf5791">
+<div class="eqlabel" id="org3f7fe1a">
 <p>
 <a id="cylgrad"></a><a href="./c_m_cs_cyl.html#cylgrad"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
-<div class="alteqlabels" id="org8187762">
+<div class="alteqlabels" id="orgcf66eee">
 <ul class="org-ul">
 <li>Gr4(1.79)</li>
 </ul>
@ -1695,14 +1695,14 @@ Range of parameters:  \(r \in [0, \infty[\), \(\varphi \in [0, 2\pi[\) and \(z \
 <div id="outline-container-c_m_cs_cyl_div" class="outline-6">
 <h6 id="c_m_cs_cyl_div"><a href="#c_m_cs_cyl_div">Divergence</a></h6>
 <div class="outline-text-6" id="text-c_m_cs_cyl_div">
-<div class="eqlabel" id="org710d9bc">
+<div class="eqlabel" id="org77a88dd">
 <p>
 <a id="cyl_div"></a><a href="./c_m_cs_cyl.html#cyl_div"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
-<div class="alteqlabels" id="org9273252">
+<div class="alteqlabels" id="orga1ce1b4">
 <ul class="org-ul">
 <li>Gr4(2.21)</li>
 </ul>
@ -1723,14 +1723,14 @@ Range of parameters:  \(r \in [0, \infty[\), \(\varphi \in [0, 2\pi[\) and \(z \
 <div id="outline-container-c_m_cs_cyl_curl" class="outline-6">
 <h6 id="c_m_cs_cyl_curl"><a href="#c_m_cs_cyl_curl">Curl</a></h6>
 <div class="outline-text-6" id="text-c_m_cs_cyl_curl">
-<div class="eqlabel" id="orgc433f93">
+<div class="eqlabel" id="orgb7e3d3b">
 <p>
 <a id="cyl_curl"></a><a href="./c_m_cs_cyl.html#cyl_curl"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
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  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
-<div class="alteqlabels" id="orgd149afb">
+<div class="alteqlabels" id="orgd068b29">
 <ul class="org-ul">
 <li>Gr4(2.21)</li>
 </ul>
@ -1779,7 +1779,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/c_m_cs_hyp.html
+++ b/build/c_m_cs_hyp.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1640,7 +1640,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/c_m_cs_sph.html
+++ b/build/c_m_cs_sph.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1631,14 +1631,14 @@ which \(r\) is the distance from the chosen origin,
 The usual Cartesian coordinates relate to spherical coordinates
 according to
 </p>
-<div class="eqlabel" id="org9ccc564">
+<div class="eqlabel" id="org3e4cc27">
 <p>
 <a id="sph_xyz"></a><a href="./c_m_cs_sph.html#sph_xyz"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
-<div class="alteqlabels" id="org7f8648f">
+<div class="alteqlabels" id="org6cfcb56">
 </div>
@ -1663,14 +1663,14 @@ A generic vector can be expressed as
 where the explicit relation between spherical and
 Cartesian unit vectors is
 </p>
-<div class="eqlabel" id="org5529443">
+<div class="eqlabel" id="org115ed32">
 <p>
 <a id="sph_uv"></a><a href="./c_m_cs_sph.html#sph_uv"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
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-<div class="alteqlabels" id="orge91c3eb">
+<div class="alteqlabels" id="org965d0cb">
 </div>
@ -1693,14 +1693,14 @@ and \(\hat{\boldsymbol \varphi} (\theta, \varphi)\).
 <p>
 An infinitesimal displacement \(d{\bf l}\) can be written as
 </p>
-<div class="eqlabel" id="orga22710f">
+<div class="eqlabel" id="orgdb194fb">
 <p>
 <a id="sph_dl"></a><a href="./c_m_cs_sph.html#sph_dl"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
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  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
-<div class="alteqlabels" id="org31d976f">
+<div class="alteqlabels" id="org96ce6ff">
 </div>
@ -1716,14 +1716,14 @@ d{\bf l} = dr ~\hat{\boldsymbol r} + r d\theta ~\hat{\boldsymbol \theta} + r\sin
 <p>
 Infinitesimal volume element:
 </p>
-<div class="eqlabel" id="org824a5cb">
+<div class="eqlabel" id="org40e244c">
 <p>
 <a id="sph_dtau"></a><a href="./c_m_cs_sph.html#sph_dtau"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
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 </svg></a>
 </p>
-<div class="alteqlabels" id="org9e40179">
+<div class="alteqlabels" id="org6796383">
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@ -1744,14 +1744,14 @@ Infinitesimal surface element:  depends on situation.
 <div id="outline-container-c_m_cs_sph_grad" class="outline-6">
 <h6 id="c_m_cs_sph_grad"><a href="#c_m_cs_sph_grad">Gradient</a></h6>
 <div class="outline-text-6" id="text-c_m_cs_sph_grad">
-<div class="eqlabel" id="orgd062ca2">
+<div class="eqlabel" id="org7c9e5d8">
 <p>
 <a id="sph_grad"></a><a href="./c_m_cs_sph.html#sph_grad"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
-<div class="alteqlabels" id="org776b74f">
+<div class="alteqlabels" id="org94fd9f5">
 </div>
@ -1768,14 +1768,14 @@ Infinitesimal surface element:  depends on situation.
 <div id="outline-container-c_m_cs_sph_div" class="outline-6">
 <h6 id="c_m_cs_sph_div"><a href="#c_m_cs_sph_div">Divergence</a></h6>
 <div class="outline-text-6" id="text-c_m_cs_sph_div">
-<div class="eqlabel" id="orgbff4022">
+<div class="eqlabel" id="org25fdd4e">
 <p>
 <a id="sph_div"></a><a href="./c_m_cs_sph.html#sph_div"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
-<div class="alteqlabels" id="orgd13f0a2">
+<div class="alteqlabels" id="org3d0214d">
 </div>
@ -1792,14 +1792,14 @@ Infinitesimal surface element:  depends on situation.
 <div id="outline-container-c_m_cs_sph_curl" class="outline-6">
 <h6 id="c_m_cs_sph_curl"><a href="#c_m_cs_sph_curl">Curl</a></h6>
 <div class="outline-text-6" id="text-c_m_cs_sph_curl">
-<div class="eqlabel" id="org4bf1642">
+<div class="eqlabel" id="org082892a">
 <p>
 <a id="sph_curl"></a><a href="./c_m_cs_sph.html#sph_curl"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
-<div class="alteqlabels" id="orge688a5a">
+<div class="alteqlabels" id="orge37528b">
 </div>
@ -1818,14 +1818,14 @@ Infinitesimal surface element:  depends on situation.
 <div id="outline-container-c_m_cs_sph_lap" class="outline-6">
 <h6 id="c_m_cs_sph_lap"><a href="#c_m_cs_sph_lap">Laplacian</a></h6>
 <div class="outline-text-6" id="text-c_m_cs_sph_lap">
-<div class="eqlabel" id="org66b8a68">
+<div class="eqlabel" id="orgf48e07a">
 <p>
 <a id="sph_Lap"></a><a href="./c_m_cs_sph.html#sph_Lap"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
-<div class="alteqlabels" id="org25a1307">
+<div class="alteqlabels" id="orge21efb8">
 </div>
@ -1859,7 +1859,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/c_m_dc.html
+++ b/build/c_m_dc.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1650,7 +1650,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/c_m_dc_curl.html
+++ b/build/c_m_dc_curl.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1652,7 +1652,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/c_m_dc_d2.html
+++ b/build/c_m_dc_d2.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1623,9 +1623,9 @@ Table of contents
 <div class="outline-text-5" id="text-c_m_dc_d2">
 </div>
-<div id="outline-container-org27b21d4" class="outline-6">
+<div id="outline-container-org3814a3d" class="outline-6">
-<h6 id="org27b21d4"><a href="#org27b21d4">Divergence of gradient</a></h6>
+<h6 id="org3814a3d"><a href="#org3814a3d">Divergence of gradient</a></h6>
-<div class="outline-text-6" id="text-org27b21d4">
+<div class="outline-text-6" id="text-org3814a3d">
 <p>
 \({\boldsymbol \nabla} \cdot ({\boldsymbol \nabla} T) \equiv {\boldsymbol \nabla}^2 T\) is called the <b>Laplacian</b> of the scalar field \(T\).
 The Laplacian of a vector field \({\boldsymbol \nabla}^2 {\bf v}\) is also defined as the vector with components
@ -1634,44 +1634,44 @@ given by the Laplacian of the corresponding vector elements.
 </div>
 </div>
-<div id="outline-container-org8ab79ed" class="outline-6">
+<div id="outline-container-orgc8aa2ed" class="outline-6">
-<h6 id="org8ab79ed"><a href="#org8ab79ed">Curl of a gradient</a></h6>
+<h6 id="orgc8aa2ed"><a href="#orgc8aa2ed">Curl of a gradient</a></h6>
-<div class="outline-text-6" id="text-org8ab79ed">
+<div class="outline-text-6" id="text-orgc8aa2ed">
 <p>
 This always vanishes.
 </p>
 </div>
 </div>
-<div id="outline-container-org3af2976" class="outline-6">
+<div id="outline-container-orge3b0dcb" class="outline-6">
-<h6 id="org3af2976"><a href="#org3af2976">Gradient of the divergence</a></h6>
+<h6 id="orge3b0dcb"><a href="#orge3b0dcb">Gradient of the divergence</a></h6>
-<div class="outline-text-6" id="text-org3af2976">
+<div class="outline-text-6" id="text-orge3b0dcb">
 <p>
 \({\boldsymbol \nabla} ({\boldsymbol \nabla} \cdot {\bf v})\) does not appear often in physics.  No special name.
 </p>
 </div>
 </div>
-<div id="outline-container-orgb2afb29" class="outline-6">
+<div id="outline-container-org1f5474a" class="outline-6">
-<h6 id="orgb2afb29"><a href="#orgb2afb29">Divergence of a curl</a></h6>
+<h6 id="org1f5474a"><a href="#org1f5474a">Divergence of a curl</a></h6>
-<div class="outline-text-6" id="text-orgb2afb29">
+<div class="outline-text-6" id="text-org1f5474a">
 <p>
 This always vanishes.
 </p>
 </div>
 </div>
-<div id="outline-container-orgd5bfcaa" class="outline-6">
+<div id="outline-container-org4b8cb79" class="outline-6">
-<h6 id="orgd5bfcaa"><a href="#orgd5bfcaa">Curl of curl</a></h6>
+<h6 id="org4b8cb79"><a href="#org4b8cb79">Curl of curl</a></h6>
-<div class="outline-text-6" id="text-orgd5bfcaa">
+<div class="outline-text-6" id="text-org4b8cb79">
-<div class="eqlabel" id="org4a8e6af">
+<div class="eqlabel" id="orgad52ac5">
 <p>
 <a id="curlcurl"></a><a href="./c_m_dc_d2.html#curlcurl"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
-<div class="alteqlabels" id="org8cfc576">
+<div class="alteqlabels" id="orgde36146">
 </div>
@ -1702,7 +1702,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/c_m_dc_del.html
+++ b/build/c_m_dc_del.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1651,7 +1651,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/c_m_dc_div.html
+++ b/build/c_m_dc_div.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1648,7 +1648,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/c_m_dc_g.html
+++ b/build/c_m_dc_g.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1672,7 +1672,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/c_m_dc_pr.html
+++ b/build/c_m_dc_pr.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1630,14 +1630,14 @@ explicited as follows:
 <p>
 <b>Gradient of a product</b>:
 </p>
-<div class="eqlabel" id="org7ccb680">
+<div class="eqlabel" id="org4bcb61a">
 <p>
 <a id="grad_prod"></a><a href="./c_m_dc_pr.html#grad_prod"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
-<div class="alteqlabels" id="orga7c6aac">
+<div class="alteqlabels" id="org8c15975">
 <ul class="org-ul">
 <li>Gr (3)</li>
 <li>W (1-111)</li>
@ -1657,14 +1657,14 @@ explicited as follows:
 <p>
 <b>Gradient of a scalar product</b>:
 </p>
-<div class="eqlabel" id="orgbe6a82f">
+<div class="eqlabel" id="org7784802">
 <p>
 <a id="grad_sprod"></a><a href="./c_m_dc_pr.html#grad_sprod"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
-<div class="alteqlabels" id="orgc2565bd">
+<div class="alteqlabels" id="orgb3682de">
 <ul class="org-ul">
 <li>Gr (4)</li>
 <li>W (1-112)</li>
@ -1684,14 +1684,14 @@ explicited as follows:
 <p>
 <b>Divergence of a product</b>:
 </p>
-<div class="eqlabel" id="org2591737">
+<div class="eqlabel" id="org96b1b94">
 <p>
 <a id="div_prod"></a><a href="./c_m_dc_pr.html#div_prod"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
-<div class="alteqlabels" id="orge3c89ac">
+<div class="alteqlabels" id="org29d8167">
 <ul class="org-ul">
 <li>Gr (5)</li>
 <li>W (1-115)</li>
@ -1711,14 +1711,14 @@ explicited as follows:
 <p>
 <b>Divergence of a cross product</b>:
 </p>
-<div class="eqlabel" id="org37cc95b">
+<div class="eqlabel" id="orgfe2b08f">
 <p>
 <a id="div_xprod"></a><a href="./c_m_dc_pr.html#div_xprod"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
-<div class="alteqlabels" id="org0277164">
+<div class="alteqlabels" id="orgdce994d">
 <ul class="org-ul">
 <li>Gr (6)</li>
 <li>W (1-116)</li>
@ -1738,14 +1738,14 @@ explicited as follows:
 <p>
 <b>Curl of a product</b>:
 </p>
-<div class="eqlabel" id="org980570b">
+<div class="eqlabel" id="orgbb8798b">
 <p>
 <a id="curl_prod"></a><a href="./c_m_dc_pr.html#curl_prod"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
-<div class="alteqlabels" id="org92e3c88">
+<div class="alteqlabels" id="org93d7ea5">
 <ul class="org-ul">
 <li>Gr (7)</li>
 <li>W (1-118)</li>
@ -1765,14 +1765,14 @@ explicited as follows:
 <p>
 <b>Curl of a cross product</b>:
 </p>
-<div class="eqlabel" id="orga4932f1">
+<div class="eqlabel" id="orgd9fde5c">
 <p>
 <a id="curl_xprod"></a><a href="./c_m_dc_pr.html#curl_xprod"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
-<div class="alteqlabels" id="org93712f0">
+<div class="alteqlabels" id="orgb1d2b5b">
 <ul class="org-ul">
 <li>Gr (8)</li>
 <li>W (1-119)</li>
@ -1813,7 +1813,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/c_m_dd.html
+++ b/build/c_m_dd.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1647,7 +1647,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/c_m_dd_1d.html
+++ b/build/c_m_dd_1d.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1659,7 +1659,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/c_m_dd_3d.html
+++ b/build/c_m_dd_3d.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1644,14 +1644,14 @@ Resolution of divergence of \(\hat{\bf r}/r^2\) paradox:
 More generally,
 </p>
-<div class="eqlabel" id="org21f3d7e">
+<div class="eqlabel" id="orgf5d25ef">
 <p>
 <a id="divdel"></a><a href="./c_m_dd_3d.html#divdel"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
-<div class="alteqlabels" id="orgeaacc49">
+<div class="alteqlabels" id="org6fba030">
 <ul class="org-ul">
 <li>Gr (1.100)</li>
 </ul>
@ -1670,14 +1670,14 @@ More generally,
 Since
 </p>
-<div class="eqlabel" id="org2f9beaa">
+<div class="eqlabel" id="org9588ee0">
 <p>
 <a id="div1or"></a><a href="./c_m_dd_3d.html#div1or"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
-<div class="alteqlabels" id="org86371cb">
+<div class="alteqlabels" id="orgb0b4434">
 <ul class="org-ul">
 <li>Gr (1.101)</li>
 </ul>
@ -1693,14 +1693,14 @@ Since
 <p>
 we have that
 </p>
-<div class="eqlabel" id="org77d9fa8">
+<div class="eqlabel" id="orgd223c1e">
 <p>
 <a id="Lap1or"></a><a href="./c_m_dd_3d.html#Lap1or"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
-<div class="alteqlabels" id="org9d70b5c">
+<div class="alteqlabels" id="org2ae8bc7">
 <ul class="org-ul">
 <li>Gr (1.102)</li>
 </ul>
@ -1732,7 +1732,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/c_m_dd_div.html
+++ b/build/c_m_dd_div.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1665,7 +1665,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/c_m_ic.html
+++ b/build/c_m_ic.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1650,7 +1650,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/c_m_ic_ftc.html
+++ b/build/c_m_ic_ftc.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1648,7 +1648,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/c_m_ic_ftg.html
+++ b/build/c_m_ic_ftg.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1657,7 +1657,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/c_m_ic_gauss.html
+++ b/build/c_m_ic_gauss.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
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 <title>Pre-Quantum Electrodynamics</title>
@ -1651,7 +1651,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/c_m_ic_ip.html
+++ b/build/c_m_ic_ip.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
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-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
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 <title>Pre-Quantum Electrodynamics</title>
@ -1658,7 +1658,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/c_m_ic_lsv.html
+++ b/build/c_m_ic_lsv.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
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 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
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 <title>Pre-Quantum Electrodynamics</title>
@ -1623,9 +1623,9 @@ Table of contents
 <div class="outline-text-5" id="text-c_m_ic_lsv">
 </div>
-<div id="outline-container-org0446f34" class="outline-6">
+<div id="outline-container-org2486563" class="outline-6">
-<h6 id="org0446f34"><a href="#org0446f34">Line Integrals</a></h6>
+<h6 id="org2486563"><a href="#org2486563">Line Integrals</a></h6>
-<div class="outline-text-6" id="text-org0446f34">
+<div class="outline-text-6" id="text-org2486563">
 <p>
 \[
 {\int_{\bf a}^{\bf b}}_{\cal P} {\bf v} \cdot d{\bf l}
@ -1654,9 +1654,9 @@ Integral over a closed loop:
 </div>
 </div>
-<div id="outline-container-org0cc3862" class="outline-6">
+<div id="outline-container-orgf44a1b8" class="outline-6">
-<h6 id="org0cc3862"><a href="#org0cc3862">Surface Integrals</a></h6>
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-<div class="outline-text-6" id="text-org0cc3862">
+<div class="outline-text-6" id="text-orgf44a1b8">
 <p>
 \[
 \int_{\cal S} {\bf v} \cdot d{\bf a}
@ -1676,9 +1676,9 @@ Over a closed surface:
 </div>
 </div>
-<div id="outline-container-orga0f7b3b" class="outline-6">
+<div id="outline-container-org7c26dcf" class="outline-6">
-<h6 id="orga0f7b3b"><a href="#orga0f7b3b">Volume Integrals</a></h6>
+<h6 id="org7c26dcf"><a href="#org7c26dcf">Volume Integrals</a></h6>
-<div class="outline-text-6" id="text-orga0f7b3b">
+<div class="outline-text-6" id="text-org7c26dcf">
 <p>
 \[
 \int_{\cal V} T d\tau
@ -1719,7 +1719,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/c_m_ic_stokes.html
+++ b/build/c_m_ic_stokes.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
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 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
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 <title>Pre-Quantum Electrodynamics</title>
@ -1621,14 +1621,14 @@ Table of contents
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 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/c_m_uf.html
+++ b/build/c_m_uf.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
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-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
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 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/c_m_uf_cyl.html
+++ b/build/c_m_uf_cyl.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
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+<!-- 2022-03-02 Wed 15:45 -->
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 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/c_m_uf_sph.html
+++ b/build/c_m_uf_sph.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
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+<!-- 2022-03-02 Wed 15:45 -->
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 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/c_m_uf_vi.html
+++ b/build/c_m_uf_vi.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
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 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
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 <title>Pre-Quantum Electrodynamics</title>
@ -1663,7 +1663,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
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 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/c_m_va.html
+++ b/build/c_m_va.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
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 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
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 <title>Pre-Quantum Electrodynamics</title>
@ -1649,7 +1649,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
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 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/c_m_va_cp.html
+++ b/build/c_m_va_cp.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
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 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
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@ -1678,7 +1678,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
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 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/c_m_va_n.html
+++ b/build/c_m_va_n.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
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 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
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@ -1673,7 +1673,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
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 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
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--- a/build/c_m_va_pds.html
+++ b/build/c_m_va_pds.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
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 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
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@ -1707,7 +1707,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
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 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
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 <p class="validation"></p>
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--- a/build/c_m_va_sp.html
+++ b/build/c_m_va_sp.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
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-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
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@ -1673,7 +1673,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
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 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
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 <p class="validation"></p>
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--- a/build/c_m_va_tp.html
+++ b/build/c_m_va_tp.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
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-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
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@ -1720,7 +1720,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
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 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
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--- a/build/c_m_vf.html
+++ b/build/c_m_vf.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
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 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
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 <title>Pre-Quantum Electrodynamics</title>
@ -1646,7 +1646,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
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 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/c_m_vf_helm.html
+++ b/build/c_m_vf_helm.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
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 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
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 <title>Pre-Quantum Electrodynamics</title>
@ -1665,7 +1665,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
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 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/c_m_vf_pot.html
+++ b/build/c_m_vf_pot.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1692,7 +1692,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/d.html
+++ b/build/d.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1622,8 +1622,8 @@ Table of contents
 </svg></a><span class="headline-id">d</span></h2>
 <div class="outline-text-2" id="text-d">
-<details class="objectives" id="orgca523dc">
+<details class="objectives" id="orge784719">
-<summary id="orgd4ff14b">
+<summary id="orgfb0d046">
 Objectives
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@ -1687,7 +1687,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/d_emd.html
+++ b/build/d_emd.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
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 <title>Pre-Quantum Electrodynamics</title>
@ -1667,7 +1667,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
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 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
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--- a/build/d_emd_ce.html
+++ b/build/d_emd_ce.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
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 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
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@ -1662,7 +1662,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
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 <div id="postamble" class="status">
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-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/d_emd_emw.html
+++ b/build/d_emd_emw.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
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 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
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 <title>Pre-Quantum Electrodynamics</title>
@ -1665,7 +1665,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
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 <div id="postamble" class="status">
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-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
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--- a/build/d_emf.html
+++ b/build/d_emf.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
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 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
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 <title>Pre-Quantum Electrodynamics</title>
@ -1662,7 +1662,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
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 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/d_ems.html
+++ b/build/d_ems.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
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 <title>Pre-Quantum Electrodynamics</title>
@ -1684,7 +1684,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
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 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
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--- a/build/d_ems_ca.html
+++ b/build/d_ems_ca.html
@ -1,7 +1,7 @@
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 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
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 <title>Pre-Quantum Electrodynamics</title>
@ -1667,7 +1667,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
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 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
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--- a/build/d_ems_ms.html
+++ b/build/d_ems_ms.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
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 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1664,7 +1664,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/d_emsm.html
+++ b/build/d_emsm.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1667,7 +1667,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/d_emsm_msm.html
+++ b/build/d_emsm_msm.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1665,7 +1665,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/d_m.html
+++ b/build/d_m.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1675,7 +1675,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/d_red.html
+++ b/build/d_red.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1669,7 +1669,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emd.html
+++ b/build/emd.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1622,8 +1622,8 @@ Table of contents
 </svg></a><span class="headline-id">emd</span></h2>
 <div class="outline-text-2" id="text-emd">
-<details class="prereq" id="org818864e">
+<details class="prereq" id="org2aba3cc">
-<summary id="org9e6a46d">
+<summary id="org30ca6a6">
 Prerequisites
 </summary>
 <ul class="org-ul">
@ -1632,8 +1632,8 @@ Prerequisites
 </ul>
 </details>
-<details class="objectives" id="org52c0d63">
+<details class="objectives" id="org98af4b0">
-<summary id="org4e1bb09">
+<summary id="org78e61da">
 Objectives
 </summary>
 <ul class="org-ul">
@ -1674,7 +1674,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emd_Fl.html
+++ b/build/emd_Fl.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1648,7 +1648,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emd_Fl_Fl.html
+++ b/build/emd_Fl_Fl.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1622,15 +1622,11 @@ Table of contents
 </svg></a><span class="headline-id">emd.Fl.Fl</span></h4>
 <div class="outline-text-4" id="text-emd_Fl_Fl">
 <p>
-1831: 3 experiments by Faraday (according to Griffiths! but it's historically incorrect)
+Around 1831, Faraday performed a number of experiments pertaining to
-\paragraph{1)} Pull a loop of wire through a magnetic field.
+the effects of time-dependent fields.
 \paragraph{2)} Move magnet around a still loop.
 \paragraph{3)} Change strength of field, holding magnet and loop still.
 </p>
 <p>
 Actually, historically, things didn't happen like that.
 The first experiment that Faraday performed (1831) involved two metal coils wound
 on opposite sides of a metal ring. When a current was turned on through the first
 coil, it generated a transient current in the second coil (as measured by a
@ -1647,27 +1643,39 @@ on this idea. Faraday observed transient current in a circuit when:
 <p>
 Faraday's big insight was to summarize these effects by noticing that
 </p>
 <p>
 \[
-  \boxed{
+\boxed{
-    \mbox{\bf A changing magnetic field induces an electric field}
+\mbox{A changing magnetic field induces an electric field.}
-  }
+}
 \]
 </p>
 <p>
 Empirically:  the changing magnetic field induces an electric current around
 the circuit. This current is really driven by an electric field having a component
 along the wire.  The line integral of this field is called the
 </p>
-<div class="core div" id="org03c55ba">
+<div class="core div" id="orgdfb0aad">
 <p>
 <b>Electromotive force (or electromotance)</b>,
-  \[
+</p>
-    {\cal E} \equiv \oint_{\cal P} {\bf E} \cdot d{\bf l}.
+<div class="eqlabel" id="org64afdaf">
-  \]
+<p>
 <a id="elmofo"></a><a href="./emd_Fl_Fl.html#elmofo"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
 <div class="alteqlabels" id="orgb3cda90">
 <ul class="org-ul">
 <li>Gr (7.9)</li>
 </ul>
 </div>
 </div>
 <p>
 \[
 {\cal E} \equiv \oint_{\cal P} {\bf E} \cdot d{\bf l}.
 \tag{elmofo}\label{elmofo}
 \]
 </p>
 </div>
@ -1676,21 +1684,56 @@ You can think of the emf in different ways. It's the energy accumulated as a uni
 </p>
 <p>
-The precise statement is that the electromotive force is proportional
+The precise statement associated to Faraday's observations
 is that the electromotive force is proportional
 to the rate of change of the magnetic flux,
 </p>
 <div class="eqlabel" id="orgec7b520">
 <p>
 <a id="Fl_flux"></a><a href="./emd_Fl_Fl.html#Fl_flux"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
 <div class="alteqlabels" id="orgf70f495">
 <ul class="org-ul">
 <li>Gr (7.14)</li>
 </ul>
 </div>
 </div>
 <p>
 \[
 {\cal E} = \oint_{\cal P} {\bf E} \cdot d{\bf l} = -\frac{d\Phi}{dt}
-\label{Gr(7.14)}
+\tag{Fl_flux}\label{Fl_flux}
 \]
 so we obtain
 </p>
-<div class="core div" id="org93f9990">
+<div class="core div" id="orgdfedc05">
 <p>
 <b>Faraday's law</b> (integral form <i>N.B.: for a stationary loop</i>)
-  \[
+</p>
-    \oint_{\cal P} {\bf E} \cdot d{\bf l} = -\int_{\cal S} \frac{\partial {\bf B}}{\partial t} \cdot d{\bf a}
+<div class="eqlabel" id="orge87df83">
-    \label{Gr(7.15)}
+<p>
-  \]
+<a id="Fl_int"></a><a href="./emd_Fl_Fl.html#Fl_int"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
 <div class="alteqlabels" id="org7b32fe7">
 <ul class="org-ul">
 <li>Gr (7.15)</li>
 </ul>
 </div>
 </div>
 <p>
 \[
 \oint_{\cal P} {\bf E} \cdot d{\bf l} = -\int_{\cal S} \frac{\partial {\bf B}}{\partial t} \cdot d{\bf a}
 \tag{Fl_int}\label{Fl_int}
 \]
 </p>
 </div>
@ -1702,20 +1745,36 @@ for any loop (on a wire or not). Using Stokes' theorem,
 \]
 we obtain
 </p>
-<div class="core div" id="org6046a76">
+<div class="core div" id="orgafa0d15">
 <div class="eqlabel" id="org13d3c14">
 <p>
 <a id="Fl"></a><a href="./emd_Fl_Fl.html#Fl"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
 <div class="alteqlabels" id="orgd662a28">
 <ul class="org-ul">
 <li>Gr (7.16)</li>
 </ul>
 </div>
 </div>
 <p>
 <b>Faraday's law</b> (differential form)
-  \[
+\[
-    {\boldsymbol \nabla} \times {\bf E} = -\frac{\partial {\bf B}}{\partial t}
+{\boldsymbol \nabla} \times {\bf E} = -\frac{\partial {\bf B}}{\partial t}
-    \label{Gr(7.16)}
+\tag{Fl}\label{Fl}
-  \]
+\]
 </p>
 </div>
 <p>
-Right-hand rule always sorts signs out.  Easier rule:  {\bf Lenz's law}, which
+Right-hand rule always sorts signs out.  Easier rule:  <b>Lenz's law</b>, which
-states that {\bf nature resists a change in flux}.  This is in fact just
+states that physical systems naturally resist a change in flux.
-{\bf Le Ch\^atelier's principle} of any action at an equilibrium point leading
+This is in fact just
 <b>Le Châtelier's principle</b> of any action at an equilibrium point leading
 to an opposing counter-reaction.
 </p>
 </div>
@ -1739,7 +1798,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emd_Fl_e.html
+++ b/build/emd_Fl_e.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1631,7 +1631,7 @@ Start from zero current, integrate in time:
 W = \frac{1}{2} L I^2
 \label{Gr(7.29)}
 \]
-Nicer way (generalizable to surface and volume currents):  from (\ref{Gr(7.25)}), flux through loop is \(\Phi = L I\).  But
+Nicer way (generalizable to surface and volume currents):  from <a href="./emd_Fl_i.html#PLI">PLI</a>, flux through loop is \(\Phi = L I\).  But
 \[
 \Phi = \int_{\cal S} {\bf B} \cdot d{\bf a} = \int_{\cal S} ({\boldsymbol \nabla} \times {\bf A}) \cdot d{\bf a}
 = \oint_{\cal P} {\bf A} \cdot d{\bf l},
@ -1647,16 +1647,16 @@ W = \frac{1}{2} I \oint {\bf A} \cdot d{\bf l} = \frac{1}{2} \oint ({\bf A} \cdo
 \]
 Generalization to volume currents:
 </p>
-<div class="eqlabel" id="org9fbfb9d">
+<div class="eqlabel" id="org87af1ba">
 <p>
 <a id="W_intAJ"></a><a href="./emd_Fl_e.html#W_intAJ"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
-<div class="alteqlabels" id="org6b3d2a5">
+<div class="alteqlabels" id="org95d3f8b">
 <ul class="org-ul">
-<li>gr (7.31)</li>
+<li>Gr (7.31)</li>
 </ul>
 </div>
@ -1664,31 +1664,22 @@ Generalization to volume currents:
 </div>
 <p>
 \[
-W = \frac{1}{2} \int_{\cal V} ({\bf A} \cdot {\bf J}) d\tau
+W = \frac{1}{2} \int_{\cal V} d\tau ~({\bf A} \cdot {\bf J})
 \tag{W_intAJ}\label{W_intAJ}
 \]
 Even better:  use Ampère, \({\boldsymbol \nabla} \times {\bf B} = \mu_0 {\bf J}\):
 \[
-W = \frac{1}{2\mu_0} \int_{\cal V} {\bf A} \cdot ({\boldsymbol \nabla} \times {\bf B}) d\tau
+W = \frac{1}{2\mu_0} \int_{\cal V} d\tau ~{\bf A} \cdot ({\boldsymbol \nabla} \times {\bf B})
 \label{Gr(7.32)}
 \]
 Integrate by parts using product rule 6:
 \[
-{\boldsymbol ∇} ⋅ ({\bf A} × {\bf B}) = {\bf B} ⋅ ({\boldsymbol ∇} × {\bf A})
+{\boldsymbol \nabla} \cdot ({\bf A} \times {\bf B}) = {\bf B} \cdot ({\boldsymbol \nabla} \times {\bf A}) - {\bf A} \cdot ({\boldsymbol \nabla} \times {\bf B}),
 </p>
 <ul class="org-ul">
 <li>{\bf A} ⋅ ({\boldsymbol ∇} × {\bf B}),</li>
 </ul>
 <p>
 \]
 so
 \[
-{\bf A} ⋅ ({\boldsymbol ∇} × {\bf B}) = {\bf B} ⋅ {\bf B}
+{\bf A} \cdot ({\boldsymbol \nabla} \times {\bf B}) =
-</p>
+{\bf B} \cdot {\bf B} - {\boldsymbol \nabla} \cdot ({\bf A} \times {\bf B}).
 <ul class="org-ul">
 <li>{\boldsymbol ∇} ⋅ ({\bf A} × {\bf B}).</li>
 </ul>
 <p>
 \]
 Then,
 \[
@ -1698,12 +1689,27 @@ W = \frac{1}{2\mu_0} \left[ \int_{\cal V} d\tau B^2 - \int_{\cal V} d\tau {\bold
 \]
 We can integrate over all space:  after neglecting boundary terms (assuming fields fall to zero at infinity), we are left with
 </p>
-<div class="core div" id="org2f4a453">
+<div class="core div" id="org247bd37">
 <div class="eqlabel" id="orgdf4c394">
 <p>
 <a id="W_intBsq"></a><a href="./emd_Fl_e.html#W_intBsq"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
 <div class="alteqlabels" id="orge069b86">
 <ul class="org-ul">
 <li>Gr (7.34)</li>
 </ul>
 </div>
 </div>
 <p>
 \[
-    W_{mag} = \frac{1}{2\mu_0} \int d\tau B^2
+W_{mag} = \frac{1}{2\mu_0} \int d\tau B^2
-    \label{Gr(7.34)}
+\tag{W_intBsq}\label{W_intBsq}
-  \]
+\]
 </p>
 </div>
@ -1713,26 +1719,38 @@ We can integrate over all space:  after neglecting boundary terms (assuming fiel
 Summary:  energy in electric and magnetic fields:
 </p>
 \begin{align}
-W_{elec} = \frac{1}{2} \int d\tau V\rho = \frac{\varepsilon_0}{2} \int d\tau E^2, \hspace{2cm}
+W_{elec} &amp;= \frac{1}{2} \int d\tau ~V\rho &amp;= \frac{\varepsilon_0}{2} \int d\tau ~E^2, \\
-\mbox{(2.43 and 2.45)}, \\
+W_{mag} &amp;= \frac{1}{2} \int d\tau ~({\bf A} \cdot {\bf J}) &amp;= \frac{1}{2\mu_0} \int d\tau ~B^2,
 W_{mag} = \frac{1}{2} \int d\tau ({\bf A} \cdot {\bf J}) = \frac{1}{2\mu_0} \int d\tau B^2,
 \hspace{2cm} \mbox{(7.31 and 7.34)}
 \end{align}
 <div class="example div" id="orgeb4514a">
 <p>
-\paragraph{Example 7.13:}  coaxial cable (inner cylinder radius \(a\), outer \(b\)) carries current \(I\).
+which are equations <a href="./ems_es_e.html#W_vcd">W_vcd</a>, <a href="./ems_es_e.html#W_intEsq">W_intEsq</a>, <a href="./emd_Fl_e.html#W_intAJ">W_intAJ</a> and <a href="./emd_Fl_e.html#W_intBsq">W_intBsq</a>.
-Find energy stored in section of length \(l\).
+</p>
-\paragraph{Solution:}  from Ampère,
+
 <div class="example div" id="org03fb4e8">
 <p>
 <b>Example: energy in coaxial cable</b>
 </p>
 <p>
 Consider a coaxial cable with inner cylinder radius \(a\), outer \(b\),
 carrying current \(I\).
 </p>
 <p>
 <b>Task</b>: find the energy stored in a section of length \(l\).
 </p>
 <p>
 <b>Solution</b>:  from Ampère,
 \[
-    {\bf B} = \frac{\mu_0 I}{2\pi s} \hat{\boldsymbol \varphi}, \hspace{1cm} a &lt; s &lt; b, \hspace{1cm}
+{\bf B} = \frac{\mu_0 I}{2\pi s} \hat{\boldsymbol \varphi}, \hspace{1cm} a &lt; s &lt; b, \hspace{1cm}
-    {\bf B} = 0, \hspace{1cm} s &lt; a ~\mbox{or}~ s &gt; b.
+{\bf B} = 0, \hspace{1cm} s &lt; a ~\mbox{or}~ s &gt; b.
-  \]
+\]
 Energy is thus
 \[
-    W_{mag} = \frac{1}{2\mu_0} \int_0^{2\pi} d\varphi \int_0^l dz \int_a^b s ds \left(\frac{\mu_0 I}{2\pi s}\right)^2
+W_{mag} = \frac{1}{2\mu_0} \int_0^{2\pi} d\varphi \int_0^l dz \int_a^b s ds \left(\frac{\mu_0 I}{2\pi s}\right)^2
-    = \frac{\mu_0 I^2 l}{4\pi} \ln \frac{b}{a}.
+= \frac{\mu_0 I^2 l}{4\pi} \ln \frac{b}{a}.
-  \]
+\]
 </p>
 </div>
@ -1758,7 +1776,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emd_Fl_i.html
+++ b/build/emd_Fl_i.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1629,7 +1629,7 @@ is (using fact that \({\bf B}_1\) is proportional to \(I_1\))
 \Phi_2 = \int {\bf B}_1 \cdot d{\bf a}_2 \Longrightarrow
 \Phi_2 = M_{21} I_1
 \]
-where \(M_{21}\) is the {\bf mutual inductance} of the two loops.
+where \(M_{21}\) is the <b>mutual inductance</b> of the two loops.
 </p>
 <p>
@ -1638,7 +1638,7 @@ Useful formula:
 \Phi_2 = \int {\bf B}_1 \cdot d{\bf a}_2 = \int ({\boldsymbol \nabla} \times {\bf A}_1) \cdot d{\bf a}_2
 = \oint {\bf A}_1 \cdot d{\bf l}_2
 \]
-But from (\ref{Gr(5.63)}),
+But from <a href="./ems_ms_vp_A.html#A_CoulG">A_CoulG</a>,
 \[
 {\bf A}_1 ({\bf r}) = \frac{\mu_0 I_1}{4\pi} \oint_{{\cal P}_1} \frac{d{\bf l}_1}{|{\bf r} - {\bf r}_1|}
 \]
@ -1647,44 +1647,89 @@ so
 \Phi_2 = \frac{\mu_0 I_1}{4\pi} \oint_{{\cal P}_2} d{\bf l}_2 \cdot
 \left(\oint_{{\cal P}_1} \frac{d{\bf l}_1 }{|{\bf r}_2 - {\bf r}_1|}\right)
 \]
-and we can write the mutual inductance as the {\bf Neumann formula},
+and we can write the mutual inductance as the <b>Neumann formula</b>,
 </p>
 <div class="eqlabel" id="org197212f">
 <p>
 <a id="Newmann_M"></a><a href="./emd_Fl_i.html#Newmann_M"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
 <div class="alteqlabels" id="org4709e6a">
 <ul class="org-ul">
 <li>Gr (7.22)</li>
 </ul>
 </div>
 </div>
 <p>
 \[
 M_{21} = \frac{\mu_0}{4\pi} \oint_{{\cal P}_1} \oint_{{\cal P}_2} \frac{d{\bf l}_1 \cdot d{\bf l}_2}
 {|{\bf r}_1 - {\bf r}_2|}
-\label{Gr(7.22)}
+\tag{Neumann_M}\label{Neumann_M}
 \]
 Two things:
 first, \(M_{21}\) is purely geometrical.  Second,
 </p>
 <div class="eqlabel" id="orgb952a44">
 <p>
 <a id="Msym"></a><a href="./emd_Fl_i.html#Msym"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
 <div class="alteqlabels" id="org53f3037">
 <ul class="org-ul">
 <li>Gr (7.23)</li>
 </ul>
 </div>
 </div>
 <p>
 \[
 M_{12} = M_{21}
-\label{Gr(7.23)}
+\tag{Msym}\label{Msym}
 \]
 </p>
-<div class="example div" id="org34dd058">
+<div class="example div" id="org6347791">
 <p>
-\paragraph{Example 7.10:}
+<b>Example: solenoid in solenoid</b>
-short solenoid (length \(l\), radius \(a\), \(n_1\) turns per unit length) lies concentrically inside
+</p>
 <p>
 Consider a short solenoid (length \(l\), radius \(a\), \(n_1\) turns per unit length)
 which lies concentrically inside
 a very long solenoid (radius \(b\), \(n_2\) turns per unit length).  Current \(I\) in short solenoid.
-What is flux through long solenoid ?
+</p>
-\paragraph{Solution:}  complicated to calculate \({\bf B}_1\).  Use mutual inductance, starting from
+
 <p>
 <b>Task</b>: compute the flux through the long solenoid.
 </p>
 <p>
 <b>Solution</b>: it's complicated to calculate \({\bf B}_1\).
 Use mutual inductance, starting from
 the reverse situation:  current \(I\) on outer solenoid, calculate flux through inner one.
-Field of outer solenoid:  from (\ref{Gr(5.57)}),
+Field of outer solenoid:  from <a href="./ems_ms_dcB_c.html#Amp_int">Amp_int</a>,
 \[
-    B = \mu_0 n_2 I
+B = \mu_0 n_2 I
-  \]
+\]
 so flux through a single loop of inner solenoid is
 \[
-    B \pi a^2 = \mu_0 n_2 I \pi a^2.
+B \pi a^2 = \mu_0 n_2 I \pi a^2.
-  \]
+\]
 For \(n_1 l\) turns in total, total flux through inner solenoid is
 \[
-    \Phi = \mu_0 \pi a^2 n_1 n_2 l I.
+\Phi = \mu_0 \pi a^2 n_1 n_2 l I.
-  \]
+\]
 Same as flux through outer solenoid if inner one has current \(I\).  Mutual inductance is here
 \[
-    M = \mu_0 \pi a^2 n_1 n_2 l.
+M = \mu_0 \pi a^2 n_1 n_2 l.
-  \]
+\]
 </p>
 </div>
@ -1697,62 +1742,101 @@ What if we vary current in loop 1?  Flux in 2 will vary.  Induces EMF in loop 2:
 \label{Gr(7.24)}
 \]
 Changing current also induces EMF in the source loop itself:
 </p>
 <div class="eqlabel" id="org667fec5">
 <p>
 <a id="PLI"></a><a href="./emd_Fl_i.html#PLI"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
 <div class="alteqlabels" id="org28a1a02">
 <ul class="org-ul">
 <li>Gr (7.25)</li>
 </ul>
 </div>
 </div>
 <p>
 \[
 \Phi = L I
-\label{Gr(7.25)}
+\tag{PLI}\label{PLI}
 \]
-where \(L\) is the {\bf self-inductance} (or inductance) of the loop.  Depends only on
+where \(L\) is the <b>self-inductance</b> (or inductance) of the loop.  Depends only on
 geometry.  Changing current induces EMF of
 \[
 {\cal E} = -L \frac{dI}{dt}
 \label{Gr(7.26)}
 \]
-Inductance:  measured in {\bf henries} (\(H\)).  \(H = V s/A\).
+Inductance:  measured in <b>henries</b> (\(H\)).  \(H = V s/A\).
 </p>
-<div class="example div" id="org7acd05e">
+<div class="example div" id="org00e72a3">
 <p>
-\paragraph{Example 7.11:}  find self-inductance of toroidal coil with
+<b>Example: self-inductance of toroidal coil</b>
 </p>
 <p>
 Consider a toroidal coil with
 rectangular cross-section (inner radius \(a\), outer radius \(b\), height \(h\))
 which carries total of \(N\) turns.
-\paragraph{Solution:}  magnetic field inside toroid is (\ref{Gr(5.58)})
+</p>
 <p>
 <b>Task</b>: find its self-inductance
 </p>
 <p>
 <b>Solution</b>:  magnetic field inside toroid is <a href="./ems_ms_dcB_c.html#Btor">Btor</a>
 \[
-    B = \frac{\mu_0 NI}{2\pi s}
+B = \frac{\mu_0 NI}{2\pi s}
-  \]
+\]
 Flux through single turn:
 \[
-    \int {\bf B} \cdot d{\bf a} = \frac{\mu_0 N I}{2\pi} h \int_a^b \frac{ds}{s}
+\int {\bf B} \cdot d{\bf a} = \frac{\mu_0 N I}{2\pi} h \int_a^b \frac{ds}{s}
-    = \frac{\mu_0 N I h}{2\pi} \ln \frac{b}{a}.
+= \frac{\mu_0 N I h}{2\pi} \ln \frac{b}{a}.
-  \]
+\]
 Total flux:  \(N\) times this, so self-inductance is
 \[
-    L = \frac{\mu_0 N^2 h}{2\pi} \ln \frac{b}{a}
+L = \frac{\mu_0 N^2 h}{2\pi} \ln \frac{b}{a}
-    \label{Gr(7.27)}
+\label{Gr(7.27)}
-  \]
+\]
 </p>
 </div>
 <p>
-Inductance (like capacitance) is intrinsically positive.  Use Lenz law.  Think of {\bf back EMF}.
+Inductance (like capacitance) is intrinsically positive.  Use Lenz law.
 Think of <i>back EMF</i>.
 </p>
-<div class="example div" id="org9f29434">
+<div class="example div" id="org958ea6c">
 <p>
-\paragraph{Example 7.12:}  circuit with inductance \(L\), resistor \(R\) and battery \({\cal E}_0\).
+<b>Example: circuit</b>
-What is the current ?
+</p>
-\paragraph{Solution:}
+
 <p>
 Consider a circuit with inductance \(L\), resistor \(R\) and battery \({\cal E}_0\).
 </p>
 <p>
 <b>Task</b>: find the current
 </p>
 <p>
 <b>Solution</b>:
 Ohm's law:
 \[
-    {\cal E}_0 - L \frac{dI}{dt} = IR \Longrightarrow I(t) = \frac{{\cal E}_0}{R} + k e^{-(R/L)t}.
+{\cal E}_0 - L \frac{dI}{dt} = IR \Longrightarrow I(t) = \frac{{\cal E}_0}{R} + k e^{-(R/L)t}.
-  \]
+\]
 If initial condition:  \(I(0) = 0\), then
 \[
-    I(t) = \frac{{\cal E}_0}{R} \left[ 1 - e^{-(R/L)t} \right]
+I(t) = \frac{{\cal E}_0}{R} \left[ 1 - e^{-(R/L)t} \right]
-    \label{Gr(7.28)}
+\label{Gr(7.28)}
-  \]
+\]
-where \(\tau \equiv L/R\) is the {\bf time constant} of the circuit.
+where \(\tau \equiv L/R\) is the <b>time constant</b> of the circuit.
 </p>
 </div>
@ -1777,7 +1861,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emd_Fl_ief.html
+++ b/build/emd_Fl_ief.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1628,7 +1628,7 @@ Two sources of electric fields:  electric charges, and changing magnetic fields.
 <p>
 Electric fields induced by a changing magnetic field are determined in an exactly
 parallel way as magnetostatic fields from the current:  exploit parallel
-between Ampère and Faraday!
+between Ampère and Faraday
 \[
 {\boldsymbol \nabla} \times {\bf B} = \mu_0 {\bf J}
 \hspace{3cm}
@ -1645,42 +1645,60 @@ law in integral form:
-<div class="example div" id="org3b5285b">
+<div class="example div" id="org045463b">
 <p>
-{\bf Example 7.7:}
+<b>Example: loop with time-dependent flux</b>
-\({\bf B}(t)\) points up in circular region of radius \(R\).  What is the induced \({\bf E}(t)\) ?
+</p>
-\paragraph{Solution:}
+
 <p>
 Consider a time-dependent magnetic field \({\bf B}(t)\) directed vertically
 through a horizontal circular region of radius \(R\).
 </p>
 <p>
 <b>Task</b>: find the induced \({\bf E}(t)\).
 </p>
 <p>
 <b>Solution</b>:
 amperian loop of radius \(s\), apply Faraday:
 \[
-    \oint {\bf E} \cdot d{\bf l} = E (2\pi s) = -\frac{d\Phi}{dt} = -\pi s^2 \frac{dB}{dt}
+\oint {\bf E} \cdot d{\bf l} = E (2\pi s) = -\frac{d\Phi}{dt} = -\pi s^2 \frac{dB}{dt}
-    \Rightarrow {\bf E} = -\frac{s}{2} \frac{dB}{dt} \hat{\boldsymbol \varphi}.
+\Rightarrow {\bf E} = -\frac{s}{2} \frac{dB}{dt} \hat{\boldsymbol \varphi}.
-  \]
+\]
 Increasing \({\bf B}\):  clockwise (viewed from above) \({\bf E}\) from Lenz.
 </p>
 </div>
-<div class="example div" id="org68f8620">
+<div class="example div" id="org047ea10">
 <p>
-{\bf Example 7.8:} wheel or radius \(b\) with line charge \(\lambda\) on the rim.
+<b>Example: wheel with charged rim traversed by flux</b>
-Uniform magnetic field \({\bf B}_0\) in central region up to \(a &lt; b\),
+</p>
-pointing up.  Field turned off.  What happens ?
+
-\paragraph{Solution:}  the wheel starts spinning to compensate the reduction of field.
+<p>
 Consider a wheel of radius \(b\) with line charge \(\lambda\) on the rim.
 A uniform magnetic field \({\bf B}_0\) pointing up is traversing the central region
 up to radius \(a &lt; b\). The field is then turned off.  What happens?
 </p>
 <p>
 <b>Solution</b>:  the wheel starts spinning to compensate the reduction of field.
 Faraday:
 \[
-    \oint {\bf E} \cdot d{\bf l} = -\frac{d\Phi}{dt} = - \pi a^2 \frac{dB}{dt}
+\oint {\bf E} \cdot d{\bf l} = -\frac{d\Phi}{dt} = - \pi a^2 \frac{dB}{dt}
-    \Rightarrow {\bf E} = -\frac{a^2}{2b} \frac{dB}{dt} \hat{\boldsymbol \varphi}.
+\Rightarrow {\bf E} = -\frac{a^2}{2b} \frac{dB}{dt} \hat{\boldsymbol \varphi}.
-  \]
+\]
 Torque on segment \(d{\bf l}\):  \(|{\bf r} \times {\bf F}| = b \lambda E dl\).
 Total torque:
 \[
-    N = b\lambda \oint E dl = -b \lambda \pi a^2 \frac{dB}{dt}
+N = b\lambda \oint E dl = -b \lambda \pi a^2 \frac{dB}{dt}
-  \]
+\]
-so total angular momentum imparted is
+so total angular momentum imparted to the wheel is
 \[
-    \int N dt = -\lambda \pi a^2 b \int_{B_0}^0 dB = \lambda \pi a^2 b B_0.
+\int N dt = -\lambda \pi a^2 b \int_{B_0}^0 dB = \lambda \pi a^2 b B_0.
-  \]
+\]
 </p>
 </div>
@ -1690,33 +1708,44 @@ The precise way the field is turned off doesn't matter.  Only electric field doe
 </p>
 <p>
-{\bf N.B.:}  we use magnetostatic formulas for changing fields.  This is
+<b>N.B.</b>:  we use magnetostatic formulas for changing fields.  This is
-called the {\bf quasistatic} approximation, and works provided we deal with
+called the <b>quasistatic</b> approximation, and works provided we deal with
-'slow enough' phenomena.
+<i>slow enough</i> phenomena.
 </p>
-<div class="example div" id="org5b14490">
+<div class="example div" id="org733cbdd">
 <p>
-{\bf Example 7.9:}  infinitely long straight wire carries \(I(t)\).  Find
+<b>Example: field from wire with time-dependent current</b>
-induced \({\bf E}\) field as a function of distance \(s\) from wire.
+</p>
-\paragraph{Solution:}  quasistatic:  magnetic field is \(B = \frac{\mu_0 I}{2\pi s}\)
+
 <p>
 Consider an infinitely long straight wire which carries current \(I(t)\).
 </p>
 <p>
 <b>Task</b>: find the induced \({\bf E}\) field as a function of distance \(s\) from wire.
 </p>
 <p>
 <b>Solution</b>:  assuming we can use the quasistatic approximation, the
 magnetic field is \(B = \frac{\mu_0 I}{2\pi s}\)
 and circles the wire.  Like \({\bf B}\) field of solenoid, \({\bf E}\) runs parallel
 to wire.  Amperian loop with sides at distances \(s_0\) and \(s\):
 \[
-    \oint {\bf E} \cdot d{\bf l} = E(s_0)l - E(s)l = -\frac{d}{dt} \int {\bf B} \cdot d{\bf a}
+\oint {\bf E} \cdot d{\bf l} = E(s_0)l - E(s)l = -\frac{d}{dt} \int {\bf B} \cdot d{\bf a}
-    = -\frac{\mu_0 l}{2\pi} \frac{dI}{dt} \int_{s_0}^s \frac{ds'}{s'}
+= -\frac{\mu_0 l}{2\pi} \frac{dI}{dt} \int_{s_0}^s \frac{ds'}{s'}
-    = -\frac{\mu_0 l}{2\pi} \frac{dI}{dt} \ln(s/s_0).
+= -\frac{\mu_0 l}{2\pi} \frac{dI}{dt} \ln(s/s_0).
-  \]
+\]
 So:
 \[
-    {\bf E} (s) = \left[ \frac{\mu_0}{2\pi} \frac{dI}{dt} \ln s + K \right] \hat{\bf x}
+{\bf E} (s) = \left[ \frac{\mu_0}{2\pi} \frac{dI}{dt} \ln s + K \right] \hat{\bf x}
-    \label{Gr(7.19)}
+\label{Gr(7.19)}
-  \]
+\]
 where \(K\) is a constant (depends on the history of \(I(t)\)).
 </p>
 <p>
-{\bf N.B.:}  this can't be true always, since it blows up as \(s \rightarrow \infty\).
+<b>N.B.</b>: this can't be true always, since it blows up as \(s \rightarrow \infty\).
 Reason:  in this case, we've overstepped the quasistatic limit.  We need
 \(s \ll c\tau\) where \(\tau\) is a typical time scale for change of \(I(t)\).
 </p>
@ -1743,7 +1772,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emd_Me.html
+++ b/build/emd_Me.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1648,7 +1648,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emd_Me_Me.html
+++ b/build/emd_Me_Me.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1624,53 +1624,79 @@ Table of contents
 <p>
 Full set of equations for the electromagnetic field:
 </p>
-<div class="core div" id="org883ebf1">
+<div class="core div" id="org40e4789">
 <p>
-{\bf Maxwell's equations} {\it (in vacuum)}
+<b>Maxwell's equations</b> <i>(in vacuum)</i>
 </p>
 <div class="eqlabel" id="org3e8ad9b">
 <p>
 <a id="Max_vac"></a><a href="./emd_Me_Me.html#Max_vac"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
 <div class="alteqlabels" id="orgc606bec">
 </div>
 </div>
 \begin{align}
-  (i) {\boldsymbol \nabla} \cdot {\bf E} &amp;= \frac{\rho}{\varepsilon_0}, \hspace{1cm} &amp;\mbox{Gauss}, \nonumber \\
+(i)~ {\boldsymbol \nabla} \cdot {\bf E} &amp;= \frac{\rho}{\varepsilon_0}, \hspace{1cm} &amp;\mbox{Gauss}, \nonumber \\
-  (ii) {\boldsymbol \nabla} \cdot {\bf B} &amp;= 0, \hspace{1cm} &amp;\mbox{anonymous} \nonumber \\
+(ii)~ {\boldsymbol \nabla} \cdot {\bf B} &amp;= 0, &amp;\mbox{anonymous} \nonumber \\
-  (iii) {\boldsymbol \nabla} \times {\bf E} &amp;= -\frac{\partial {\bf B}}{\partial t}, \hspace{1cm} &amp;\mbox{Faraday}, \nonumber \\
+(iii)~ {\boldsymbol \nabla} \times {\bf E} &amp;= -\frac{\partial {\bf B}}{\partial t}, &amp;\mbox{Faraday}, \nonumber \\
-  (iv) {\boldsymbol \nabla} \times {\bf B} &amp;= \mu_0 {\bf J} + \mu_0 \varepsilon_0 \frac{\partial {\bf E}}{\partial t}, \hspace{1cm} &amp;\mbox{Ampère + Maxwell}.
+(iv)~ {\boldsymbol \nabla} \times {\bf B} &amp;= \mu_0 {\bf J} + \mu_0 \varepsilon_0 \frac{\partial {\bf E}}{\partial t}, &amp;\mbox{Ampère + Maxwell}.
-  \label{Gr(7.39)}
+\tag{Max_vac}\label{Max_vac}
 \end{align}
 </div>
 <p>
 Complement:
 </p>
-<div class="core div" id="org2481694">
+<div class="core div" id="org28daec0">
 <p>
-{\bf Force law}
+Force law <a href="./ems_ms_lf_pc.html#LorFo">LorFo</a>
 \[
-    {\bf F} = q ({\bf E} + {\bf v} \times {\bf B}).
+{\bf F} = q ({\bf E} + {\bf v} \times {\bf B}).
-    \label{Gr(7.40)}
+\label{Gr(7.40)}
-  \]
+\]
 </p>
 </div>
 <p>
-These equations summarize the {\bf entire content of classical electrodynamics}.
+These equations contain the <b>entirety of pre-quantum electrodynamics</b>.
 </p>
 <p>
-\paragraph{Note:}  even the continuity equation can be derived from Maxwell's equations:
+<b>Note</b>:  even the continuity equation can be derived from Maxwell's equations:
-take divergence of \((iv)\).
+take divergence of \((iv)\) and use \((i)\).
 </p>
 <p>
 Better way of writing:  all fields on left, all sources on right,
 </p>
-<div class="core div" id="org47f05c2">
+<div class="core div" id="org4bb3e78">
 <div class="eqlabel" id="org05437e5">
 <p>
 <a id="Max_vac_s"></a><a href="./emd_Me_Me.html#Max_vac_s"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
 <div class="alteqlabels" id="org61742b2">
 <ul class="org-ul">
 <li>Gr (7.42)</li>
 </ul>
 </div>
 </div>
 \begin{align}
-  (i) &amp;{\boldsymbol \nabla} \cdot {\bf E} = \frac{\rho}{\varepsilon_0},
+(i)~ {\boldsymbol \nabla} \cdot {\bf E} &amp;= \frac{\rho}{\varepsilon_0}, \nonumber \\
-  &amp;(iii) {\boldsymbol \nabla} \times {\bf E} + \frac{\partial {\bf B}}{\partial t} = 0, \\
+(ii)~{\boldsymbol \nabla} \cdot {\bf B} &amp;= 0, \nonumber \\
-  (ii) &amp;{\boldsymbol \nabla} \cdot {\bf B} = 0,
+(iii)~ {\boldsymbol \nabla} \times {\bf E} + \frac{\partial {\bf B}}{\partial t} &amp;= 0, \nonumber \\
-  &amp;(iv) {\boldsymbol \nabla} \times {\bf B} - \mu_0 \varepsilon_0 \frac{\partial {\bf E}}{\partial t} = \mu_0 {\bf J},
+(iv)~ {\boldsymbol \nabla} \times {\bf B} - \mu_0 \varepsilon_0 \frac{\partial {\bf E}}{\partial t} &amp;= \mu_0 {\bf J},
-  \label{Gr(7.42)}
+\tag{Max_vac_s}\label{Max_vac_s}
 \end{align}
 </div>
@ -1679,6 +1705,7 @@ Better way of writing:  all fields on left, all sources on right,
 <br><ul class="navigation-links"><li>Prev:&nbsp;<a href="emd_Me_dc.html">Maxwell's Correction to Ampère's Law; the Displacement Current&emsp;<small>[emd.Me.dc]</small></a></li><li>Next:&nbsp;<a href="emd_Me_mc.html">Magnetic Charge&emsp;<small>[emd.Me.mc]</small></a></li><li>Up:&nbsp;<a href="emd_Me.html">Maxwell's Equations&emsp;<small>[emd.Me]</small></a></li></ul>
 <br>
 <hr>
@ -1694,7 +1721,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emd_Me_dc.html
+++ b/build/emd_Me_dc.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1622,8 +1622,7 @@ Table of contents
 </svg></a><span class="headline-id">emd.Me.dc</span></h4>
 <div class="outline-text-4" id="text-emd_Me_dc">
 <p>
-The term which should be zero (but isn't) in (\ref{Gr(7.35)}) can be rewritten using
+The term which should be zero (but isn't) in <a href="./emd_Me_ebM.html#divcurlB">divcurlB</a> can be rewritten using the continuity equation as
 the continuity equation as
 \[
 {\boldsymbol \nabla} \cdot {\bf J} = -\frac{\partial \rho}{\partial t} = - \frac{\partial}{\partial t}
 (\varepsilon_0 {\boldsymbol \nabla} \cdot {\bf E}) = -{\boldsymbol \nabla} \cdot \left(
@ -1631,37 +1630,67 @@ the continuity equation as
 \]
 The extra term would thus be eliminated if we were to put
 </p>
-<div class="core div" id="orgb95d862">
+<div class="core div" id="orgdf7b3f9">
 <div class="eqlabel" id="org5844c7b">
 <p>
 <a id="AmpMax"></a><a href="./emd_Me_dc.html#AmpMax"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
 <div class="alteqlabels" id="org1e192cc">
 <ul class="org-ul">
 <li>Gr (7.36)</li>
 </ul>
 </div>
 </div>
 <p>
 \[
-    {\boldsymbol \nabla} \times {\bf B} = \mu_0 {\bf J} + \mu_0 \varepsilon_0 \frac{\partial {\bf E}}{\partial t}
+{\boldsymbol \nabla} \times {\bf B} = \mu_0 {\bf J} + \mu_0 \varepsilon_0 \frac{\partial {\bf E}}{\partial t}
-    \label{Gr(7.36)}
+\tag{AmpMax}\label{AmpMax}
-  \]
+\]
 </p>
 </div>
 <p>
-\paragraph{Note:}  this changes nothing in magnetostatics.  Aesthetic appeal:
+<b>Note</b>:  this changes nothing in magnetostatics.  Aesthetic appeal:
 \[
-  \boxed{
+\boxed{
-    \mbox{A changing electric field induces a magnetic field.}
+\mbox{A changing electric field induces a magnetic field.}
-  }
+}
 \]
 Real confirmation of Maxwell's theory:  1888, Hertz's experiments on propagation of electromagnetic waves.
 </p>
 <p>
 Maxwell baptized this term the
 </p>
-<div class="core div" id="orgb8b014a">
+<div class="core div" id="orgb28580f">
 <p>
 <b>Displacement current</b>
 </p>
 <div class="eqlabel" id="org4a72dcc">
 <p>
 <a id="Jd"></a><a href="./emd_Me_dc.html#Jd"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
 <div class="alteqlabels" id="org57849e1">
 <ul class="org-ul">
 <li>Gr (7.37)</li>
 </ul>
 </div>
 </div>
 <p>
 {\bf Displacement current}
 \[
-    {\bf J}_d \equiv \varepsilon_0 \frac{\partial {\bf E}}{\partial t}.
+{\bf J}_d \equiv \varepsilon_0 \frac{\partial {\bf E}}{\partial t}.
-    \label{Gr(7.37)}
+\tag{Jd}\label{Jd}
-  \]
+\]
 </p>
 </div>
@ -1675,7 +1704,7 @@ where \(A\) is the area.  Between the plates,
 \[
 \frac{\partial E}{\partial t} = \frac{1}{\varepsilon_0 A} \frac{dQ}{dt} = \frac{1}{\varepsilon_0 A} I.
 \]
-Checking (\ref{Gr(7.36)}),
+Checking <a href="./emd_Me_dc.html#AmpMax">AmpMax</a>,
 \[
 \oint {\bf B} \cdot d{\bf l} = \mu_0 I_{\mbox{enc}} + \mu_0 \varepsilon_0 \int d{\bf a} \cdot \frac{\partial {\bf E}}{\partial t}
 \label{Gr(7.38)}
@ -1703,7 +1732,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emd_Me_ebM.html
+++ b/build/emd_Me_ebM.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1625,10 +1625,10 @@ Table of contents
 We've encountered:
 </p>
 \begin{align}
-(i) &amp;{\boldsymbol \nabla} \cdot {\bf E} = \frac{\rho}{\varepsilon_0}, \hspace{1cm} &amp;\mbox{Gauss}, \nonumber \\
+(i)~ {\boldsymbol \nabla} \cdot {\bf E} &amp;= \frac{\rho}{\varepsilon_0}, \hspace{1cm} &amp;\mbox{Gauss}, \nonumber \\
-(ii) &amp;{\boldsymbol \nabla} \cdot {\bf B} = 0, \hspace{1cm} &amp;\mbox{anonymous} \nonumber \\
+(ii)~ {\boldsymbol \nabla} \cdot {\bf B} &amp;= 0, &amp;\mbox{anonymous} \nonumber \\
-(iii) &amp;{\boldsymbol \nabla} \times {\bf E} = -\frac{\partial {\bf B}}{\partial t}, \hspace{1cm} &amp;\mbox{Faraday}, \nonumber \\
+(iii)~ {\boldsymbol \nabla} \times {\bf E} &amp;= -\frac{\partial {\bf B}}{\partial t},  &amp;\mbox{Faraday}, \nonumber \\
-(iv) &amp;{\boldsymbol \nabla} \times {\bf B} = \mu_0 {\bf J}, \hspace{1cm} &amp;\mbox{Ampère}.
+(iv)~ {\boldsymbol \nabla} \times {\bf B} &amp;= \mu_0 {\bf J}, &amp;\mbox{Ampère}.
 \end{align}
 <p>
 Fatal inconsistency:  div of curl must always vanish.  Check on \((iii)\):
@ -1637,11 +1637,28 @@ Fatal inconsistency:  div of curl must always vanish.  Check on \((iii)\):
 = {\boldsymbol \nabla} \cdot \left( -\frac{\partial {\bf B}}{\partial t} \right) = -\frac{\partial}{\partial t} ({\boldsymbol \nabla} \cdot {\bf B}) = 0.
 \]
 But:  try same with \((iv)\):
 </p>
 <div class="eqlabel" id="org764ac3e">
 <p>
 <a id="divcurlB"></a><a href="./emd_Me_ebM.html#divcurlB"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
 <div class="alteqlabels" id="org0f4f12d">
 <ul class="org-ul">
 <li>Gr (7.35)</li>
 </ul>
 </div>
 </div>
 <p>
 \[
 {\boldsymbol \nabla} \cdot ({\boldsymbol \nabla} \times {\bf B}) = \mu_0 {\boldsymbol \nabla} \cdot {\bf J}
-\label{Gr(7.35)}
+\tag{divcurlB}\label{divcurlB}
 \]
-LHS must be zero, but RHS is not zero for non-steady currents.  Cannot be right !
+LHS must be zero, but RHS is not zero for non-steady currents.  Cannot be right!
 </p>
 <p>
@ -1673,7 +1690,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emd_Me_mc.html
+++ b/build/emd_Me_mc.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1633,7 +1633,7 @@ In free space, where \(\rho\) and \({\bf J}\) vanish:
 <p>
 Symmetry:  replace \({\bf E}\) by \({\bf B}\) and \({\bf B}\) by \(-\mu_0 \varepsilon_0{\bf E}\) in the first pair.
 They turn into the second pair.  This symmetry is spoiled by \(\rho\) and \({\bf J}\).  What if we had
-a truly symmetric situation, {\it i.e.}
+a truly symmetric situation, <i>i.e.</i>
 </p>
 \begin{align}
 (i) &amp;{\boldsymbol \nabla} \cdot {\bf E} = \frac{\rho_e}{\varepsilon_0},
@ -1650,7 +1650,7 @@ of magnetic charge.  Both charges would be conserved:
 {\boldsymbol \nabla} \cdot {\bf J}_e = -\frac{\partial \rho_e}{\partial t}.
 \label{Gr(7.44)}
 \]
-Maxwell's equations {\bf beg} for magnetic charges.  But we've never found any!
+Maxwell's equations <i>beg</i> for magnetic charges.  But we've never found any!
 </p>
 </div>
 </div>
@ -1671,7 +1671,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emd_ce.html
+++ b/build/emd_ce.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1622,8 +1622,8 @@ Table of contents
 </svg></a><span class="headline-id">emd.ce</span></h3>
 <div class="outline-text-3" id="text-emd_ce">
-<details class="prereq" id="org70c43f6">
+<details class="prereq" id="orgca631bc">
-<summary id="org3522c33">
+<summary id="org2ad112f">
 Prerequisites
 </summary>
 <ul class="org-ul">
@ -1631,8 +1631,8 @@ Prerequisites
 </ul>
 </details>
-<details class="objectives" id="orgead6b14">
+<details class="objectives" id="orgbdb48d8">
-<summary id="orgf683e76">
+<summary id="org495ffbc">
 Objectives
 </summary>
 <ul class="org-ul">
@ -1670,7 +1670,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emd_ce_amom.html
+++ b/build/emd_ce_amom.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1624,14 +1624,29 @@ Table of contents
 <p>
 The angular momentum of EM fields is directly given by
 </p>
-<div class="main div" id="orgaa57ede">
+<div class="main div" id="org6e52344">
 <p>
 <b>Angular momentum of EM fields</b>
 </p>
 <div class="eqlabel" id="org9b249c7">
 <p>
 <a id="lrxg"></a><a href="./emd_ce_amom.html#lrxg"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
 <div class="alteqlabels" id="org9913b19">
 </div>
 </div>
 <p>
 {\bf Angular momentum of EM fields}
 \[
-    {\boldsymbol l} = {\boldsymbol r} \times {\boldsymbol g}
+{\boldsymbol l} = {\boldsymbol r} \times {\boldsymbol g}
-    = \varepsilon_0 {\boldsymbol r} \times
+= \varepsilon_0 ~{\boldsymbol r} \times
-    \left({\boldsymbol E} \times {\boldsymbol B}\right)
+\left({\boldsymbol E} \times {\boldsymbol B}\right)
-  \]
+\tag{lrxg}\label{lrxg}
 \]
 </p>
 </div>
@ -1654,7 +1669,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emd_ce_ce.html
+++ b/build/emd_ce_ce.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1622,13 +1622,13 @@ Table of contents
 </svg></a><span class="headline-id">emd.ce.ce</span></h4>
 <div class="outline-text-4" id="text-emd_ce_ce">
 <p>
-Very important distinction:  {\bf global} versus {\bf local} conservation of charge.
+Very important distinction:  <b>global</b> versus <b>local</b> conservation of charge.
 </p>
 <p>
-Charge in a volume {\cal V}:
+Charge in a volume \({\cal V}\):
 \[
-Q_{\cal V} (t) = \int_{\cal V} d\tau \rho ({\bf r}, t)
+Q_{\cal V} (t) = \int_{\cal V} d\tau~ \rho ({\bf r}, t)
 \label{Gr(8.1)}
 \]
 Current \({\bf J}\) flowing out through boundary \({\cal S}\) of \({\cal V}\):  conservation of charge means
@ -1643,13 +1643,12 @@ This means that
 \]
 Since this is true for any volume, we have (re)derived the
 </p>
-<div class="core div" id="orgfb5850b">
+<div class="core div" id="orgf1c2b2a">
 <p>
-{\bf Continuity equation}
+<b>Continuity equation</b> <a href="./ems_ms_ce.html#conteq">conteq</a>
 \[
-    \frac{\partial \rho}{\partial t} + {\boldsymbol \nabla} \cdot {\bf J} = 0
+\frac{\partial \rho}{\partial t} + {\boldsymbol \nabla} \cdot {\bf J} = 0
-    \label{Gr(8.4)}
+\]
  \]
 </p>
 </div>
@ -1660,7 +1659,7 @@ Therefore, conservation of charge is a direct consequence of Maxwell's equations
 <p>
 One thing to note: we have viewed \(\rho\) and \({\boldsymbol J}\) as sources
 (the ''right-hand side'') of Maxwell's equations. The continuity equation thus
-imposes a functional constraint on these sources: not {\it any} \(\rho\) and
+imposes a functional constraint on these sources: not <i>any</i> \(\rho\) and
 \({\boldsymbol J}\) will do the trick, only the ones what obey it.
 </p>
 </div>
@ -1684,7 +1683,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emd_ce_mom.html
+++ b/build/emd_ce_mom.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1624,7 +1624,7 @@ Table of contents
 <p>
 From Newton's second law,
 \[
-  {\boldsymbol F} = \frac{d {\boldsymbol p}_{\tiny \mbox{mech}}}{dt}
+{\boldsymbol F} = \frac{d {\boldsymbol p}_{\tiny \mbox{mech}}}{dt}
 \]
 we have
 \[
@ -1636,24 +1636,54 @@ in which the first integral can be interpreted as the momentum stored in the EM
 <p>
 This is thus simply a conservation law for momentum, with
 </p>
-<div class="main div" id="orgc75d196">
+<div class="main div" id="orgecd6647">
 <p>
 <b>Momentum density in the EM fields</b>
 </p>
 <div class="eqlabel" id="orga1d9e2c">
 <p>
 <a id="gExB"></a><a href="./emd_ce_mom.html#gExB"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
 <div class="alteqlabels" id="orgf73a06d">
 </div>
 </div>
 <p>
 {\bf Momentum density in the EM fields}
 \[
-    {\boldsymbol g} = \varepsilon_0 \mu_0 {\boldsymbol S} = \varepsilon_0 {\boldsymbol E} \times {\boldsymbol B}
+{\boldsymbol g} = \varepsilon_0 \mu_0 {\boldsymbol S} = \varepsilon_0 {\boldsymbol E} \times {\boldsymbol B}
-  \]
+\tag{gExB}\label{gExB}
 \]
 </p>
 </div>
 <p>
 In a region in which the mechanical momentum is not changing due to external influences, we then have the
 </p>
-<div class="main div" id="orgc680b5b">
+<div class="main div" id="org8cc6bb8">
 <p>
 <b>Continuity equation for EM momentum</b>
 </p>
 <div class="eqlabel" id="orgcad090e">
 <p>
 <a id="contg"></a><a href="./emd_ce_mom.html#contg"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
 <div class="alteqlabels" id="org69cf28d">
 </div>
 </div>
 <p>
 {\bf Continuity equation for EM momentum}
 \[
-    \frac{\partial}{\partial t} {\boldsymbol g} - {\boldsymbol \nabla} \cdot {\boldsymbol T} = 0
+\frac{\partial}{\partial t} {\boldsymbol g} - {\boldsymbol \nabla} \cdot {\boldsymbol T} = 0
-  \]
+\tag{contg}\label{contg}
 \]
 </p>
 </div>
@ -1677,7 +1707,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emd_ce_mst.html
+++ b/build/emd_ce_mst.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1638,30 +1638,27 @@ Substitute for \(\rho\) and \({\boldsymbol J}\) using Maxwell (Gauss and Ampère
 <p>
 On the other hand we have
 \[
  \frac{\partial }{\partial t} \left( {\boldsymbol E} × {\boldsymbol B} \right)
  = \frac{∂ {\boldsymbol E}}{∂ t} × {\boldsymbol B}
 </p>
-<ul class="org-ul">
+\begin{equation}
-<li>{\boldsymbol E} × \frac{∂ {\boldsymbol B}}{∂ t}.</li>
+  \frac{\partial }{\partial t} \left( {\boldsymbol E} \times {\boldsymbol B} \right)
-</ul>
+  = \frac{\partial {\boldsymbol E}}{\partial t} \times {\boldsymbol B}
  + {\boldsymbol E} \times \frac{\partial {\boldsymbol B}}{\partial t}.
 \end{equation}
 <p>
 \]
 Using Faraday to substitute for \(\frac{\partial {\boldsymbol B}}{\partial t}\),
 \[
  \frac{ ∂ {\boldsymbol E}}{∂ t} × {\boldsymbol B}
  = \frac{\partial }{\partial t} \left( {\boldsymbol E} × {\boldsymbol B}\right)
 </p>
-<ul class="org-ul">
+\begin{equation}
-<li>{\boldsymbol E} × \left({\boldsymbol ∇} × {\boldsymbol E} \right)</li>
+  \frac{ \partial {\boldsymbol E}}{\partial t} \times {\boldsymbol B}
-</ul>
+  = \frac{\partial }{\partial t} \left( {\boldsymbol E} \times {\boldsymbol B}\right)
  + {\boldsymbol E} \times \left({\boldsymbol \nabla} \times {\boldsymbol E} \right)
 \end{equation}
 <p>
 \]
 so
 \[
  {\boldsymbol f} = \varepsilon_0 \left( \left( {\boldsymbol \nabla} \cdot {\boldsymbol E} \right) {\boldsymbol E} - {\boldsymbol E} \times \left( {\boldsymbol \nabla} \times {\boldsymbol E} \right) \right) - \frac{1}{\mu_0} \left( {\boldsymbol B} \times \left( {\boldsymbol \nabla} \times {\boldsymbol B} \right) \right) - \varepsilon_0 \frac{\partial}{\partial t} \left( {\boldsymbol E} \times {\boldsymbol B} \right).
 \]
-Since \({\boldsymbol \nabla} \cdot {\boldsymbol B} = 0\), we can symmetrize the expression in \({\boldsymbol E}\) and \({\boldsymbol B}\). Moreover, by product rule 4,
+Since \({\boldsymbol \nabla} \cdot {\boldsymbol B} = 0\), we can symmetrize the expression in \({\boldsymbol E}\) and \({\boldsymbol B}\).
 Moreover, by <a href="./c_m_dc_pr.html#grad_sprod">grad_sprod</a>,
 \[
  \frac{1}{2}{\boldsymbol \nabla} \left( E^2 \right) = \left( {\boldsymbol E} \cdot {\boldsymbol \nabla} \right) {\boldsymbol E} + {\boldsymbol E} \times \left( {\boldsymbol \nabla} \times {\boldsymbol E} \right)
 \]
@ -1678,18 +1675,27 @@ and similarly for \({\boldsymbol B}\). We thus get
 <p>
 This expression can be greatly simplified by introducing the
 </p>
-<div class="main div" id="org41d984c">
+<div class="main div" id="orga7d370d">
 <p>
-{\bf Maxwell stress tensor}
+<b>Maxwell stress tensor</b>
 \[
  T_{ij} ≡ ε_0 \left( E_i E_j - \frac{1}{2} δ_{ij} E^2\right)
 </p>
-<ul class="org-ul">
+<div class="eqlabel" id="orge5429c3">
 <li>\frac{1}{\mu_0} \left( B_i B_j - \frac{1}{2} δ_{ij} B^2 \right)</li>
 </ul>
 <p>
-\]
+<a id="MaxST"></a><a href="./emd_ce_mst.html#MaxST"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
 <div class="alteqlabels" id="org0306495">
 </div>
 </div>
 \begin{equation}
 T_{ij} \equiv \varepsilon_0 \left( E_i E_j - \frac{1}{2} \delta_{ij} E^2\right)
    + \frac{1}{\mu_0} \left( B_i B_j - \frac{1}{2} \delta_{ij} B^2 \right)
 \tag{MaxST}\label{MaxST}
 \end{equation}
 </div>
 <p>
@ -1699,26 +1705,56 @@ The element \(T_{ij}\) represents the force per unit area in the $i$th direction
 <p>
-We then obtain
+We then obtain the
 </p>
-<div class="main div" id="orgefc4ae2">
+<div class="main div" id="org4781d10">
 <p>
 <b>EM force per unit volume</b>
 </p>
 <div class="eqlabel" id="orgd9f91b7">
 <p>
 <a id="fT"></a><a href="./emd_ce_mst.html#fT"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
 <div class="alteqlabels" id="org7d4a06b">
 </div>
 </div>
 <p>
 {\bf EM force per unit volume}
 \[
-    {\boldsymbol f} = {\boldsymbol \nabla} \cdot {\boldsymbol T} - \varepsilon_0 \mu_0 \frac{\partial {\boldsymbol S}}{\partial t}
+{\boldsymbol f} = {\boldsymbol \nabla} \cdot {\boldsymbol T} - \varepsilon_0 \mu_0 \frac{\partial {\boldsymbol S}}{\partial t}
-  \]
+\tag{fT}\label{fT}
 \]
 </p>
 </div>
 <p>
 where \({\boldsymbol S}\) is the Poynting vector. Integrating, we obtain the
 </p>
-<div class="main div" id="orgc9bf6dd">
+<div class="main div" id="orgea18677">
 <p>
 <b>Total force on charges in volume</b>
 </p>
 <div class="eqlabel" id="orgef98657">
 <p>
 <a id="totFo"></a><a href="./emd_ce_mst.html#totFo"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
 <div class="alteqlabels" id="org4c9c200">
 </div>
 </div>
 <p>
 {\bf Total force on charges in volume}
 \[
-    {\boldsymbol F} = \oint_S {\boldsymbol T} \cdot d{\boldsymbol a} - \varepsilon_0 \mu_0 \frac{d}{dt} \int_{\cal V} {\boldsymbol S} d\tau.
+{\boldsymbol F} = \oint_S {\boldsymbol T} \cdot d{\boldsymbol a} - \varepsilon_0 \mu_0 \frac{d}{dt} \int_{\cal V} {\boldsymbol S} d\tau.
-  \]
+\tag{totFo}\label{totFo}
 \]
 </p>
 </div>
@ -1742,7 +1778,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emd_ce_poy.html
+++ b/build/emd_ce_poy.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1638,38 +1638,45 @@ Total energy should be sum of these two.  Derivation from scratch.
 <p>
 Suppose that at time \(t\), we have fields \({\bf E}\) and \({\bf B}\) produced by some charge
 and current distributions \(\rho\) and \({\bf J}\).  In an interval \(dt\), how much work is
-done by EM forces ?  From Lorentz force law:
+done by EM forces?  From Lorentz force law:
 \[
 {\bf F} \cdot d{\bf l} = q({\bf E} + {\bf v} \times {\bf B}) \cdot {\bf v} dt = q ~{\bf E} \cdot {\bf v} dt
 \]
 Really, we're looking at a small volume element \(d\tau\) carrying charge \(\rho d\tau\), moving
 at velocity \({\bf v}\) such that \({\bf J} = \rho {\bf v}\).  Thus,
 </p>
 <div class="eqlabel" id="org0197499">
 <p>
 <a id="dWdt_intEJ"></a><a href="./emd_ce_poy.html#dWdt_intEJ"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
 <div class="alteqlabels" id="org9aacea3">
 <ul class="org-ul">
 <li>Gr (8.6)</li>
 </ul>
 </div>
 </div>
 <p>
 \[
 \frac{dW}{dt} = \int_{\cal V} d\tau ~ {\bf E} \cdot {\bf J}
-\label{Gr(8.6)}
+\tag{dWdt_intEJ}\label{dWdt_intEJ}
 \]
 The integrand is the work done per unit time, per unit volume, {\it i.e.} the power delivered per unit volume.
 In terms of fields alone:  use Ampère-Maxwell:
 \[
 {\bf E} \cdot {\bf J} = \frac{1}{\mu_0} {\bf E} \cdot ({\boldsymbol \nabla} \times {\bf B}) - \varepsilon_0 {\bf E} \cdot \frac{\partial {\bf E}}{\partial t}
 \]
-Using product rule 6,
+Using <a href="./c_m_dc_pr.html#div_xprod">div_xprod</a>,
 \[
-{\boldsymbol ∇} ⋅ ({\bf E} × {\bf B}) = {\bf B} ⋅ ({\boldsymbol ∇} × {\bf E})
+{\boldsymbol \nabla} \cdot ({\bf E} \times {\bf B}) = {\bf B} \cdot ({\boldsymbol \nabla} \times {\bf E}) - {\bf E} \cdot ({\boldsymbol \nabla} \times {\bf B}),
 </p>
 <ul class="org-ul">
 <li>{\bf E} ⋅ ({\boldsymbol ∇} × {\bf B}),</li>
 </ul>
 <p>
 \]
 Invoking Faraday \({\boldsymbol \nabla} \times {\bf E} = - \partial {\bf B}/\partial t\),
 \[
-{\bf E} ⋅ ({\boldsymbol ∇} × {\bf B}) = - {\bf B} ⋅ \frac{∂ {\bf B}}{∂ t}
+{\bf E} \cdot ({\boldsymbol \nabla} \times {\bf B}) = - {\bf B} \cdot \frac{\partial {\bf B}}{\partial t} - {\boldsymbol \nabla} \cdot ({\bf E} \times {\bf B}).
 </p>
 <ul class="org-ul">
 <li>{\boldsymbol ∇} ⋅ ({\bf E} × {\bf B}).</li>
 </ul>
 <p>
 \]
 But obviously,
 \[
@ -1679,28 +1686,35 @@ But obviously,
 \]
 so we get
 \[
-{\bf E} ⋅ {\bf J} = -\frac{1}{2} \frac{\partial}{\partial t} \left( ε_0 E^2 + \frac{1}{\mu_0} B^2 \right)
+{\bf E} \cdot {\bf J} = -\frac{1}{2} \frac{\partial}{\partial t} \left( \varepsilon_0 E^2 + \frac{1}{\mu_0} B^2 \right) - \frac{1}{\mu_0} {\boldsymbol \nabla} \cdot ({\bf E} \times {\bf B}).
 </p>
 <ul class="org-ul">
 <li>\frac{1}{\mu_0} {\boldsymbol ∇} ⋅ ({\bf E} × {\bf B}).</li>
 </ul>
 <p>
 \label{Gr(8.8)}
 \]
-Substituting this in \ref{Gr(8.6)} and using the divergence theorem,
+Substituting this in <a href="./emd_ce_poy.html#dWdt_intEJ">dWdt_intEJ</a> and using the divergence theorem,
 we obtain
 </p>
-<div class="main div" id="orgda8af3a">
+<div class="main div" id="orgf118f4f">
 <p>
-{\bf Poynting's theorem}
+<b>Poynting's theorem</b>
 \[
  \frac{dW}{dt} = -\frac{d}{d t} ∫_{\cal V} dτ \frac{1}{2} \left( ε_0 E^2 + \frac{1}{\mu_0} B^2 \right)
 </p>
-<ul class="org-ul">
+<div class="eqlabel" id="org1b7cdac">
 <li>\frac{1}{\mu_0} \oint_{\cal S} d{\bf a} ⋅ ({\bf E} × {\bf B})</li>
 </ul>
 <p>
-  \label{Gr(8.9)}
+<a id="👉Thm"></a><a href="./emd_ce_poy.html#👉Thm"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
 <div class="alteqlabels" id="orgd7b6cac">
 <ul class="org-ul">
 <li>Gr (8.9)</li>
 </ul>
 </div>
 </div>
 <p>
 \[
 \frac{dW}{dt} = -\frac{d}{d t} \int_{\cal V} d\tau \frac{1}{2} \left( \varepsilon_0 E^2 + \frac{1}{\mu_0} B^2 \right) - \frac{1}{\mu_0} \oint_{\cal S} d{\bf a} \cdot ({\bf E} \times {\bf B})
 \tag{👉Thm}\label{👉Thm}
 \]
 </p>
@ -1713,41 +1727,92 @@ energy is carried by EM fields out of \({\cal V}\) across its boundary surface.
 <p>
-Energy per unit time, per unit area carried by EM fields:
+Energy per unit time, per unit area carried by EM fields: given by the
 </p>
-<div class="core div" id="org8a1c10e">
+<div class="core div" id="orgf3198a5">
 <p>
 <b>Poynting vector</b>
 </p>
 <div class="eqlabel" id="org8725431">
 <p>
 <a id="PoyntingVec"></a><a href="./emd_ce_poy.html#PoyntingVec"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
 <div class="alteqlabels" id="org6f2879d">
 <ul class="org-ul">
 <li>Gr (8.10)</li>
 </ul>
 </div>
 </div>
 <p>
 {\bf Poynting vector}
 \[
-    {\bf S} \equiv \frac{1}{\mu_0} ({\bf E} \times {\bf B})
+{\bf S} \equiv \frac{1}{\mu_0} ({\bf E} \times {\bf B})
-    \label{Gr(8.10)}
+\tag{PoyntingVec}\label{PoyntingVec}
-  \]
+\]
 </p>
 </div>
 <p>
 We can thus express Poynting's theorem more compactly:
 </p>
-<div class="core div" id="org57576be">
+<div class="core div" id="org3a4bb91">
 <p>
 <b>Poynting's theorem</b> (integral form)
 </p>
 <div class="eqlabel" id="orgbf2cc63">
 <p>
 <a id="PoyntingThm_int"></a><a href="./emd_ce_poy.html#PoyntingThm_int"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
 <div class="alteqlabels" id="org5f484e3">
 <ul class="org-ul">
 <li>Gr (8.11)</li>
 </ul>
 </div>
 </div>
 <p>
 {\bf Poynting's theorem}
 \[
-    \frac{dW}{dt} = - \frac{dU_{em}}{dt} - \oint_{\cal S} d{\bf a} \cdot {\bf S}.
+\frac{dW}{dt} = - \frac{dU_{em}}{dt} - \oint_{\cal S} d{\bf a} \cdot {\bf S}.
-    \label{Gr(8.11)}
+\tag{PoyntingThm_int}\label{PoyntingThm_int}
-  \]
+\]
 </p>
 </div>
 <p>
 where we have defined the total
 </p>
-<div class="core div" id="org43eb64b">
+<div class="core div" id="orgbc7eb16">
 <p>
 <b>Energy in electromagnetic fields</b>
 </p>
 <div class="eqlabel" id="org89872c3">
 <p>
 <a id="Uem"></a><a href="./emd_ce_poy.html#Uem"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
 <div class="alteqlabels" id="org67613ca">
 <ul class="org-ul">
 <li>Gr (8.5)</li>
 </ul>
 </div>
 </div>
 <p>
 {\bf Energy in electromagnetic fields}
 \[
-    U_{em} \equiv \frac{1}{2} \int d\tau \left( \varepsilon_0 E^2 + \frac{1}{\mu_0} B^2 \right)
+U_{em} \equiv \frac{1}{2} \int d\tau \left( \varepsilon_0 E^2 + \frac{1}{\mu_0} B^2 \right)
-    \label{Gr(8.5)}
+\tag{Uem}\label{Uem}
-  \]
+\]
 </p>
 </div>
@ -1764,13 +1829,30 @@ Then,
 \]
 so we get the
 </p>
-<div class="core div" id="org29b53c2">
+<div class="core div" id="org487db23">
 <p>
 <b>Poynting theorem</b> (differential form)
 </p>
 <div class="eqlabel" id="org9593699">
 <p>
 <a id="PoyntingThm"></a><a href="./emd_ce_poy.html#PoyntingThm"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
 <div class="alteqlabels" id="org129becb">
 <ul class="org-ul">
 <li>Gr (8.14)</li>
 </ul>
 </div>
 </div>
 <p>
 {\bf Poynting theorem (differential form)}
 \[
-    \frac{\partial}{\partial t} u_{em} + {\boldsymbol \nabla} \cdot {\bf S} = 0
+\frac{\partial}{\partial t} u_{em} + {\boldsymbol \nabla} \cdot {\bf S} = 0
-    \label{Gr(8.14)}
+\tag{PoyntingThm}\label{PoyntingThm}
-  \]
+\]
 </p>
 </div>
@ -1781,26 +1863,38 @@ and has a similar for to the continuity equation
-<div class="example div" id="orgbb7ac4b">
+<div class="example div" id="orgd9e0ab5">
 <p>
 <b>Example:  Joule heating</b>
 </p>
 <p>
 <b>Task</b>: characterize the energy flow for a current-carrying wire.
 </p>
 <p>
 <b>Solution</b>:  the energy per unit time delivered to wire the wire can
 be obtained from Poynting's theorem.
 </p>
 <p>
 \paragraph{Example 8.1}  Current in a wire:  Joule heating.  Energy per unit time delivered to wire:  from Poynting.
 Assuming that the field is uniform, the electric field parallel to the wire is
 \[
-    {\boldsymbol E} = \frac{V}{L} \hat{\boldsymbol x},
+{\boldsymbol E} = \frac{V}{L} \hat{\boldsymbol x},
-  \]
+\]
 where \(V\) is the potential difference between the ends ald \(L\) is the length.  Magnetic field is circumferential:
 wire of radius \(a\),
 \[
-    {\boldsymbol B} = \frac{\mu_0 I}{2\pi a} \hat{\boldsymbol \varphi}
+{\boldsymbol B} = \frac{\mu_0 I}{2\pi a} \hat{\boldsymbol \varphi}
-  \]
+\]
 Poynting:
 \[
-    {\boldsymbol S} = \frac{1}{\mu_0} \frac{V}{L} \frac{\mu_0 I}{2\pi a} \hat{\boldsymbol x} \times \hat{\boldsymbol \varphi} = -\frac{VI}{2\pi a L} \hat{\boldsymbol s}
+{\boldsymbol S} = \frac{1}{\mu_0} \frac{V}{L} \frac{\mu_0 I}{2\pi a} \hat{\boldsymbol x} \times \hat{\boldsymbol \varphi} = -\frac{VI}{2\pi a L} \hat{\boldsymbol s}
-  \]
+\]
 and points radially inwards.  Energy per unit time passing surface of wire:
 \[
-    \int d{\bf a} \cdot {\bf S} = S (2\pi a L) = -V I
+\int d{\bf a} \cdot {\bf S} = S (2\pi a L) = -V I
-  \]
+\]
 where the minus sign means energy is flowing {\it in} (the wire heats up),
 and the value is as expected.
 </p>
@ -1826,7 +1920,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emd_emw.html
+++ b/build/emd_emw.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1622,8 +1622,8 @@ Table of contents
 </svg></a><span class="headline-id">emd.emw</span></h3>
 <div class="outline-text-3" id="text-emd_emw">
-<details class="prereq" id="org9d74d32">
+<details class="prereq" id="orgd522e84">
-<summary id="org175f28d">
+<summary id="org3c8d630">
 Prerequisites
 </summary>
 <ul class="org-ul">
@ -1632,8 +1632,8 @@ Prerequisites
 </ul>
 </details>
-<details class="objectives" id="org73ffbc8">
+<details class="objectives" id="org98124eb">
-<summary id="org638d300">
+<summary id="org6546918">
 Objectives
 </summary>
 <ul class="org-ul">
@ -1674,7 +1674,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emd_emw_ep.html
+++ b/build/emd_emw_ep.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1652,7 +1652,7 @@ so for a monochromatic EM plan wave,
 \]
 or more succinctly:
 </p>
-<div class="main div" id="org677cdf7">
+<div class="main div" id="org0e45759">
 <p>
 {\bf Poynting vector of a monochromatic EM wave}
 \[
@ -1668,7 +1668,7 @@ This has a transparent physical interpretation: the energy density \(u\) flows w
 <p>
 Similary, we get the
 </p>
-<div class="main div" id="orgc6fc8e6">
+<div class="main div" id="org4b55ff9">
 <p>
 {\bf Momentum density of a monochromatic EM wave}
 \[
@ -1719,7 +1719,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emd_emw_mpw.html
+++ b/build/emd_emw_mpw.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1653,7 +1653,7 @@ B_0 = \frac{k}{\omega} E_0 = \frac{1}{c} E_0.
 Generalizing to propagation in the direction of an arbitrary wavevector
 \({\boldsymbol k}\) and (transverse) polarization vector \(\hat{\boldsymbol n}\), we have the
 </p>
-<div class="core div" id="orgd2950da">
+<div class="core div" id="org53e84bf">
 <p>
 {\bf E and B fields for a monochromatic EM plane wave}
 \[
@ -1697,7 +1697,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emd_emw_we.html
+++ b/build/emd_emw_we.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1650,7 +1650,7 @@ These take the form of coupled first-order partial differential equations for \(
 Since \({\boldsymbol \nabla} \cdot {\bf E} = 0\) and \({\boldsymbol \nabla} \cdot {\bf B} = 0\),
 we get the
 </p>
-<div class="core div" id="org88fc1e4">
+<div class="core div" id="orgb3cd985">
 <p>
 {\bf Wave equations for electric and magnetic fields in vacuum}
 \[
@ -1706,7 +1706,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emdm.html
+++ b/build/emdm.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1646,7 +1646,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emdm_Me.html
+++ b/build/emdm_Me.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1646,7 +1646,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emdm_Me_Mem.html
+++ b/build/emdm_Me_Mem.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1657,7 +1657,7 @@ dI = \frac{\partial \sigma_b}{\partial t} da_{\perp} = \frac{\partial P}{\partia
 \]
 We therefore have the
 </p>
-<div class="core div" id="org9606db6">
+<div class="core div" id="org0421a72">
 <p>
 {\bf Polarization current density}
 \[
@ -1675,7 +1675,7 @@ the polarization current is the result of linear motion of charge when
 polarization changes).  We can check consistency with the continuity equation
 associated to the conservation of bound charges:
 </p>
-<aside id="orge1ae7f1">
+<aside id="org642846e">
 <p>
 Note the unfortunate labelling: it would have been nicer to have \(\rho_b\) be the charge associated to current
  \({\boldsymbol J}_b\) but this is not the convention used here.
@ -1698,7 +1698,7 @@ Changing magnetization does not lead to analogous accumulation of charge and cur
 In view of this:  total charge density can be separated into 2 parts,
 {\it free} and {\it bound}:
 </p>
-<div class="main div" id="orgb0d00db">
+<div class="main div" id="orgba471ef">
 <p>
 \[
    \rho = \rho_f + \rho_b = \rho_f - {\boldsymbol \nabla} \cdot {\bf P}
@ -1711,7 +1711,7 @@ In view of this:  total charge density can be separated into 2 parts,
 and current can be separated into three parts, {\it free}, {\it bound} and
 {\it polarization}:
 </p>
-<div class="main div" id="org89c562c">
+<div class="main div" id="org2ffd81b">
 <p>
 \[
  {\bf J} = {\bf J}_f + {\bf J}_b + {\bf J}_p = {\bf J}_f + {\boldsymbol ∇} × {\bf M}
@ -1735,7 +1735,7 @@ Gauss's law:  can be rewritten
 \]
 where (as in static case)
 </p>
-<div class="core div" id="org0196779">
+<div class="core div" id="org88bb3c5">
 <p>
 \[
    {\bf D} \equiv \varepsilon_0 {\bf E} + {\bf P}
@ -1761,7 +1761,7 @@ or
 \]
 where as before
 </p>
-<div class="core div" id="org2b5f6d5">
+<div class="core div" id="org90cea20">
 <p>
 \[
    {\bf H} \equiv \frac{1}{\mu_0} {\bf B} - {\bf M}
@ -1779,7 +1779,7 @@ bound parts, since they don't involve \(\rho\) or \({\bf J}\).
 <p>
 In terms of free charges and currents, we thus get
 </p>
-<div class="core div" id="org2c2cd2a">
+<div class="core div" id="orgd6526ab">
 <p>
 {\bf Maxwell's equations {\it (in matter)}}
 </p>
@ -1805,7 +1805,7 @@ Must be complemented by the {\bf constitutive relations} giving \({\bf D}\) and
 in terms of \({\bf E}\) and \({\bf B}\).
 For the restricted case of linear media:
 </p>
-<div class="main div" id="orgcaf59d5">
+<div class="main div" id="orgd345cd6">
 <p>
 \[
    {\bf P} = \varepsilon_0 \chi_e {\bf E}, \hspace{1cm}
@ -1842,7 +1842,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emdm_Me_bc.html
+++ b/build/emdm_Me_bc.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1624,7 +1624,7 @@ Table of contents
 <p>
 Discontinuities between different media, deduced from
 </p>
-<div class="core div" id="orgc82cb6f">
+<div class="core div" id="org48bc400">
 <p>
 {\bf Maxwell's equations {\it (in matter)}, integral form}
 </p>
@ -1715,7 +1715,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emdm_emwm.html
+++ b/build/emdm_emwm.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1649,7 +1649,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emdm_emwm_ad.html
+++ b/build/emdm_emwm_ad.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1645,7 +1645,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emdm_emwm_ad_c.html
+++ b/build/emdm_emwm_ad_c.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1741,7 +1741,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emdm_emwm_plm.html
+++ b/build/emdm_emwm_plm.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1659,7 +1659,7 @@ v = \frac{1}{\sqrt{\mu \varepsilon}} = \frac{c}{n}
 \]
 where the index of refraction of the material is defined as
 </p>
-<div class="main div" id="orga0b7fe5">
+<div class="main div" id="orgd0bce92">
 <p>
 {\bf Index of refraction}
 \[
@ -1716,7 +1716,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emdm_emwm_refl.html
+++ b/build/emdm_emwm_refl.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1660,7 +1660,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emdm_emwm_refl_Ba.html
+++ b/build/emdm_emwm_refl_Ba.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1640,7 +1640,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emdm_emwm_refl_Fe.html
+++ b/build/emdm_emwm_refl_Fe.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1641,7 +1641,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emdm_emwm_refl_ni.html
+++ b/build/emdm_emwm_refl_ni.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1732,7 +1732,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emdm_emwm_refl_oi.html
+++ b/build/emdm_emwm_refl_oi.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1659,7 +1659,7 @@ These forms for incident, reflected and transmitted wave can be substituted in t
 <p>
 From now on we will orient the axes so that \({\boldsymbol k}_I\) lies in the \(xz\) plane. This means that \({\boldsymbol k}_R\) and \({\boldsymbol k}_T\) also lie in that plane. This is the
 </p>
-<div class="core div" id="orgab5561c">
+<div class="core div" id="orge681e56">
 <p>
 {\bf First law of reflection:}
 the incident, reflected and transmitted wave vectors form a plane (called the plane of incidence) which also includes the normal to the surface.
@ -1674,7 +1674,7 @@ Specializing (\ref{eq:RTObliquek}) to our notations, we have
 with the incidence (\(\theta_I\)) and reflection (\(\theta_R\)) angles
 and the angle of refraction (\(\theta_T\)) obey the following laws:
 </p>
-<div class="core div" id="orgfe980d3">
+<div class="core div" id="orgfbf5032">
 <p>
 {\bf Law of reflection}
 \[
@ -1732,7 +1732,7 @@ while the third equation becomes
 \]
 Writing everything in terms of the incident amplitude, we get
 </p>
-<div class="main div" id="org3d560e5">
+<div class="main div" id="orgcf2803c">
 <p>
 {\bf Fresnel's equations for reflection and transmission amplitudes (parallel case)}
 \[
@ -1752,7 +1752,7 @@ Amplitudes for transmitted and reflected wave: depend on angle of incidence:
 Behaviour: for \(\theta_I = 0\) we recover (\ref{Gr(9.82)}).
 For grazing waves \(\theta_I \rightarrow \pi/2\) we have that \(\alpha \rightarrow \infty\) and the wave is totally reflected. The most interesting angle is the one at which \(\alpha = \beta\) and the reflected wave has zero amplitude. This is known as
 </p>
-<div class="main div" id="org88a1e03">
+<div class="main div" id="org7503b43">
 <p>
 {\bf Brewster's angle {\it (at which the reflected wave amplitude vanishes)}}
  \[
@ -1802,7 +1802,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emdm_emwm_refr.html
+++ b/build/emdm_emwm_refr.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1641,7 +1641,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emdm_emwm_wg.html
+++ b/build/emdm_emwm_wg.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1647,7 +1647,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emdm_emwm_wg_c.html
+++ b/build/emdm_emwm_wg_c.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1667,7 +1667,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emdm_emwm_wg_gw.html
+++ b/build/emdm_emwm_wg_gw.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1691,7 +1691,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emdm_emwm_wg_r.html
+++ b/build/emdm_emwm_wg_r.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1700,7 +1700,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emf.html
+++ b/build/emf.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1622,8 +1622,8 @@ Table of contents
 </svg></a><span class="headline-id">emf</span></h2>
 <div class="outline-text-2" id="text-emf">
-<details class="prereq" id="orgb740c0e">
+<details class="prereq" id="orgb93b9c3">
-<summary id="org919d213">
+<summary id="org621593e">
 Prerequisites
 </summary>
 <ul class="org-ul">
@ -1631,8 +1631,8 @@ Prerequisites
 </ul>
 </details>
-<details class="objectives" id="orgd6caf8f">
+<details class="objectives" id="org179e7b9">
-<summary id="org998f38c">
+<summary id="orgb47e5d6">
 Objectives
 </summary>
 <ul class="org-ul">
@ -1668,7 +1668,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emf_g.html
+++ b/build/emf_g.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1665,7 +1665,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emf_g_Cg.html
+++ b/build/emf_g_Cg.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1664,7 +1664,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emf_g_Lg.html
+++ b/build/emf_g_Lg.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1637,7 +1637,7 @@ while the equation for \(V\) becomes
 \]
 These can be written compactly upon introducing a new operator: the
 </p>
-<div class="core div" id="org892bf92">
+<div class="core div" id="org242c17e">
 <p>
 {\bf d'Alembertian operator}
 \[
@ -1650,7 +1650,7 @@ These can be written compactly upon introducing a new operator: the
 <p>
 so we get the
 </p>
-<div class="core div" id="org2f9d40b">
+<div class="core div" id="orgb00ab8a">
 <p>
 {\bf Inhomogeneous Maxwell equations (Lorenz gauge)}
 \[
@ -1700,7 +1700,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/emf_svp.html
+++ b/build/emf_svp.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1638,7 +1638,7 @@ Useful strategy: represent fields in terms of potentials.
 <p>
 Easiest:
 </p>
-<div class="core div" id="org94d8659">
+<div class="core div" id="orgf88fb96">
 <p>
 \[
    {\boldsymbol B} = {\boldsymbol \nabla} \times {\boldsymbol A}
@ -1654,7 +1654,7 @@ Putting this into Faraday's law gives
 \]
 so this can be written as the gradient of a scalar (by choice: \(-{\boldsymbol \nabla} V\)) so we get
 </p>
-<div class="core div" id="org61bab66">
+<div class="core div" id="org2f23671">
 <p>
 \[
    {\boldsymbol E} = -{\boldsymbol \nabla} V - \frac{\partial {\boldsymbol A}}{\partial t}
@ -1667,7 +1667,7 @@ so this can be written as the gradient of a scalar (by choice: \(-{\boldsymbol \
 <p>
 Using this potential representation for \({\boldsymbol E}\) and \({\boldsymbol B}\) automatically fulfills the two homogeneous Maxwell equations. For the inhomogeneous equations, substituting (\ref{eq:E_from_Potentials}) into Gauss's law gives
 </p>
-<div class="main div" id="orga59d0cc">
+<div class="main div" id="org5127f9c">
 <p>
 \[
    {\boldsymbol \nabla}^2 V + \frac{\partial}{\partial t} {\boldsymbol \nabla} \cdot {\boldsymbol A} = -\frac{\rho}{\varepsilon_0}
@ -1683,7 +1683,7 @@ whereas Amp{\`ere}-Maxwell becomes
 \]
 which becomes after simple rearrangement and use of the identity \({\boldsymbol \nabla} \times \left({\boldsymbol \nabla} \times {\boldsymbol A}\right) = {\boldsymbol \nabla} ({\boldsymbol \nabla} \cdot {\boldsymbol A}) - {\boldsymbol \nabla}^2 {\boldsymbol A}\),
 </p>
-<div class="main div" id="org514d3f1">
+<div class="main div" id="org3f2c1f0">
 <p>
 \[
  \left( {\boldsymbol ∇}^2 {\boldsymbol A} - μ_0 ε_0 \frac{∂^2 {\boldsymbol A}}{∂ t^2} \right)
@ -1719,7 +1719,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/ems.html
+++ b/build/ems.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1648,7 +1648,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/ems_ca.html
+++ b/build/ems_ca.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1626,8 +1626,8 @@ Table of contents
 <li>Gr 3</li>
 </ul>
-<details class="prereq" id="org3402c83">
+<details class="prereq" id="org3b926ab">
-<summary id="org4cf0fe6">
+<summary id="org2707d3f">
 Prerequisites
 </summary>
 <ul class="org-ul">
@ -1635,8 +1635,8 @@ Prerequisites
 </ul>
 </details>
-<details class="objectives" id="org9645228">
+<details class="objectives" id="orgfae12c2">
-<summary id="orgc4935b9">
+<summary id="org18515f0">
 Objectives
 </summary>
 <ul class="org-ul">
@ -1674,7 +1674,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/ems_ca_fe.html
+++ b/build/ems_ca_fe.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1632,7 +1632,7 @@ A generic configuration of static charges coupled via the Coulomb interaction
 defines an electrostatic problem, whose solution is in principle obtained
 from calculating either the field according to <a href="./ems_es_ef_ccd.html#E_vcd">E_vcd</a>
 </p>
-<div class="main div" id="orgca99451">
+<div class="main div" id="orgbb90bd9">
 <p>
 </p>
@ -1646,7 +1646,7 @@ from calculating either the field according to <a href="./ems_es_ef_ccd.html#E_v
 or (often simpler) by calculating the electrostatic potential, using either the
 explicit construction <a href="./ems_es_ep_d.html#p_vcd">p_vcd</a>
 </p>
-<div class="main div" id="orge64dc41">
+<div class="main div" id="org9f1e898">
 <p>
 </p>
@ -1666,7 +1666,7 @@ condition <a href="./ems_es_ef_cE.html#curlE0">curlE0</a> can be expressed as th
 <a href="./ems_es_ep_PL.html#Poi">🐟</a>
 </p>
-<div class="core div" id="orgd88f849">
+<div class="core div" id="org7c70185">
 <p>
 </p>
@ -1682,7 +1682,7 @@ condition <a href="./ems_es_ef_cE.html#curlE0">curlE0</a> can be expressed as th
 <p>
 In the specific case where the charge density vanishes, we fall back onto the simpler Laplace equation <a href="./ems_es_ep_PL.html#Lap">Lap</a>
 </p>
-<div class="core div" id="orgfefb816">
+<div class="core div" id="org1935b19">
 <p>
 </p>
@ -1720,7 +1720,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/ems_ca_fe_L.html
+++ b/build/ems_ca_fe_L.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1638,14 +1638,14 @@ In one dimension, the potential is a single-variable
 function \(\phi (x)\) and the Laplace equation reads
 </p>
-<div class="eqlabel" id="org46aafa7">
+<div class="eqlabel" id="org84cc03f">
 <p>
 <a id="Lap_1d"></a><a href="./ems_ca_fe_L.html#Lap_1d"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
-<div class="alteqlabels" id="org459093f">
+<div class="alteqlabels" id="org61fa4ec">
 </div>
@ -1660,14 +1660,14 @@ function \(\phi (x)\) and the Laplace equation reads
 <p>
 The solution to this is
 </p>
-<div class="eqlabel" id="orged9e79a">
+<div class="eqlabel" id="orgb8c4067">
 <p>
 <a id="Lap_1d_sol"></a><a href="./ems_ca_fe_L.html#Lap_1d_sol"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
-<div class="alteqlabels" id="org599dad5">
+<div class="alteqlabels" id="org6b2acba">
 <ul class="org-ul">
 <li>Gr (3.6)</li>
 </ul>
@ -1726,14 +1726,14 @@ In two dimensions, the potential becomes a function
 of two variables (here: \(x\) and \(y\)), so Laplace's
 equation now reads
 </p>
-<div class="eqlabel" id="orgdc4453f">
+<div class="eqlabel" id="orgf3e1009">
 <p>
 <a id="Lap_2d"></a><a href="./ems_ca_fe_L.html#Lap_2d"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
-<div class="alteqlabels" id="org259268b">
+<div class="alteqlabels" id="org696fc74">
 </div>
@ -1786,14 +1786,14 @@ a point equals its value averaged over a sphere
 \(S_R({\bf r})\) of any radius \(R\) centered on this point
 (and of course not containing any charges),
 </p>
-<div class="eqlabel" id="org822a974">
+<div class="eqlabel" id="org9f81e63">
 <p>
 <a id="p_ball_avg"></a><a href="./ems_ca_fe_L.html#p_ball_avg"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
-<div class="alteqlabels" id="org57d10c8">
+<div class="alteqlabels" id="org66bdc2f">
 </div>
@ -1805,8 +1805,8 @@ a point equals its value averaged over a sphere
 \]
 </p>
-<details id="org0d796b5">
+<details id="org0f27c64">
-<summary id="org6d53cda">
+<summary id="org881e712">
 <strong>Physicist's proof</strong>
 </summary>
 <p>
@ -1868,8 +1868,8 @@ proving the theorem.
 </p>
 </details>
-<details id="org68c57fd">
+<details id="org0dbbb13">
-<summary id="org5db3c01">
+<summary id="orgf2b7c76">
 <strong>Formal proof</strong>
 </summary>
@ -1919,14 +1919,14 @@ we get the following general
 <p>
 <b>Theorem</b>:
 </p>
-<div class="eqlabel" id="org59c453b">
+<div class="eqlabel" id="org230e535">
 <p>
 <a id="dfdR_intLap"></a><a href="./ems_ca_fe_L.html#dfdR_intLap"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
-<div class="alteqlabels" id="org9481971">
+<div class="alteqlabels" id="org37e5ede">
 </div>
@ -1979,19 +1979,19 @@ are necessarily positive, we thus require \(f_x &gt; 0\), \(f_y &gt; 0\) and \(f
 of the \(f_x + f_y + f_z = 0\) condition above.
 </p>
-<div class="eqlabel" id="org81bf520">
+<div class="eqlabel" id="org8692599">
 <p>
 <a id="Earnshaw"></a><a href="./ems_ca_fe_L.html#Earnshaw"><svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-link" viewBox="0 0 16 16">
  <path d="M6.354 5.5H4a3 3 0 0 0 0 6h3a3 3 0 0 0 2.83-4H9c-.086 0-.17.01-.25.031A2 2 0 0 1 7 10.5H4a2 2 0 1 1 0-4h1.535c.218-.376.495-.714.82-1z"/>
  <path d="M9 5.5a3 3 0 0 0-2.83 4h1.098A2 2 0 0 1 9 6.5h3a2 2 0 1 1 0 4h-1.535a4.02 4.02 0 0 1-.82 1H12a3 3 0 1 0 0-6H9z"/>
 </svg></a>
 </p>
-<div class="alteqlabels" id="orgf2a161c">
+<div class="alteqlabels" id="orgcae1a27">
 </div>
 </div>
-<div class="info div" id="orgd9c5641">
+<div class="info div" id="orgab38e5b">
 <p>
 <b>Earnshaw's theorem (physical version)</b> <br>
 </p>
@ -2018,7 +2018,7 @@ Going back to Poisson's equation, we can make a few comments:
 <p>
 We therefore want to ask the question:  <i>under what conditions can an electrostatic problem be fully
-defined by solving Poisson's equation ?</i>
+defined by solving Poisson's equation?</i>
 </p>
 <p>
@ -2087,7 +2087,7 @@ their maximal and minimal value on the boundary, we must have \(U = 0\) \(\foral
 <p>
-This all feels a bit amateurish and not very systematic. Can we be more precise and general?  What kinds of boundary information do we really need to specify the solution uniquely ?
+This all feels a bit amateurish and not very systematic. Can we be more precise and general?  What kinds of boundary information do we really need to specify the solution uniquely?
 </p>
 </div>
 </div>
@ -2110,7 +2110,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
 </div>
 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
 <p class="validation"></p>
 </div>
--- a/build/ems_ca_fe_g.html
+++ b/build/ems_ca_fe_g.html
@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-<!-- 2022-03-01 Tue 08:14 -->
+<!-- 2022-03-02 Wed 15:45 -->
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Pre-Quantum Electrodynamics</title>
@ -1621,11 +1621,11 @@ Table of contents
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 <p>
 <b>George Green</b>
 </p>
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 <p>
 See a <a href="https://en.wikipedia.org/wiki/George%5C_Green%5C_(mathematician)">short bio on wikipedia</a>
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@ -1658,14 +1658,14 @@ and
 \]
 Substituting this in the divergence theorem gives <b>Green's first identity</b>
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 <li>J (1.34)</li>
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@ -1683,14 +1683,14 @@ As an aside for now, for completeness, if we do the same thing again but with \(
 interchanged, and subtract the result, we obtain another useful result known as
 <b>Green's second identity</b> or <b>Green's theorem</b>
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 <li>J (1.35)</li>
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@ -1726,7 +1726,7 @@ target="_blank">Creative Commons Attribution 4.0 International License</a>.
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 <div id="postamble" class="status">
 <p class="author">Author: Jean-Sébastien Caux</p>
-<p class="date">Created: 2022-03-01 Tue 08:14</p>
+<p class="date">Created: 2022-03-02 Wed 15:45</p>
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