update postface

pglpm · Sep 9, 2024 · 5b057dc · 5b057dc
1 parent 04804e8
commit 5b057dc
Show file tree

Hide file tree

Showing 4 changed files with 7 additions and 5 deletions.
diff --git a/docs/seven-wonders.pdf b/docs/seven-wonders.pdf
diff --git a/seven-wonders.pdf b/seven-wonders.pdf
diff --git a/seven-wonders.tex b/seven-wonders.tex
@@ -2,7 +2,7 @@
 \pdfinclusioncopyfonts=1
 %% Author: PGL  Porta Mana
 %% Created: 2015-05-01T20:53:34+0200
-%% Last-Updated: 2024-09-09T15:19:49+0200
+%% Last-Updated: 2024-09-09T19:03:45+0200
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 \newif\ifanon
 \anonfalse
@@ -9104,7 +9104,9 @@ \subsection{Constraints on constitutive relations for friction}
 
 Newtonian point-mass mechanics is less and less used in astronomy as well. Ephemerides use post-Newtonian approximations of general relativity \parencites{parketal2021}. NASA and the \furl{https://www.jpl.nasa.gov}{Jet Propulsion Laboratory} by default include relativistic effects \parencites{moyer2000} when they plan or calculate trajectories for Earth, Moon, and beyond. The same general-relativistic formulae are used to calculate and plan spacecraft dynamics, for navigating in \furl{https://csps.aerospace.org/papers/cislunar-development-what-build-and-why}{cis-lunar} or geocentric space as well as for interplanetary missions: the same software is used for navigating in both regimes \parencites{parketal2024}.
 
-The student is, in other words, introduced to notions and a physical understanding that cannot be used \enquote{as is} but will instead require revisions -- some of which quite drastic. I say this out of my own experience as a physics student, researcher, and teacher.
+Fourth, science and education have had the noble tradition of founding their teachings on the notions of the theories that proved to be most correct. That is how we got Newtonian mechanics and electromagnetics in our schools. Today we know that Newtonian mechanics and some of its intuitions are only approximate; whereas the predictions and explanations offered by general relativity (and quantum theory) keep on being beautifully confirmed. It's time we continue our noble tradition and replace those Newtonian notions that are only approximate with more exact ones.
+
+The student is, in other words, introduced to notions and a physical understanding that are partially incorrect, according to our present understanding of physics, and that moreover cannot be used \enquote{as is}, but will instead require revisions -- some of which quite drastic (I say this out of my own experience as a physics student, researcher, and teacher).
 
   % "Yes, NASA/JPL include relativistic effects when we plan or calculate trajectories for Earth, Moon, and beyond.  The same PPN (parameterized post-Newtonian) metric is used to calculate and plan spacecraft dynamics.  For example, if we don’t include the relativistic effect, GPS orbits will be not as good as what we have now." Ryan Park, Group Supervisor of JPL's Solar System Dynamics Group
   % 
@@ -9113,9 +9115,9 @@ \subsection{Constraints on constitutive relations for friction}
 
 \medskip
 
-One might hear the argument that the teaching approach via Newtonian point-mass mechanics is closer to \enquote{everyday intuition}. But that's a topsy-turvy argument: Our everyday intuition comes from that teaching approach. As an analogy, someone in the 16th century could have said that it's better to teach the \furl{https://www.britannica.com/science/geocentric-model}{geocentric model} of the solar system, than the heliocentric one, because the former is closer to everyday intuition. Yet our children today quickly develop a heliocentric intuition, simply because it's the one that enters our education from the start. Similar arguments could be made for other concepts, such as energy, that once were not part of everyday intuition, but today are.
+One might hear the argument that the teaching approach via Newtonian point-mass mechanics is closer to \enquote{everyday intuition}. But that's a topsy-turvy argument: Our everyday intuition comes from that teaching approach. As an analogy, someone in the 16th century could have said that it's better to teach the \furl{https://www.britannica.com/science/geocentric-model}{geocentric model} of the solar system, than the heliocentric one, because the former is closer to everyday intuition. Yet our children today quickly develop a heliocentric intuition, simply because it's the one that enters our education from the start. Similar arguments could be made for other concepts, such as energy or the electromagnetic field, that once were not part of everyday intuition, but today are.
 
-\section{The validity of the mathematical form of the balance laws in general relativity}
+\addsubsec{The validity of the mathematical form of the balance laws in general relativity}
 \label{sec:balances_GR}
 
 These notes state several times that the mathematical form of the equation for balance, for instance

diff --git a/seven-wonders.toc b/seven-wonders.toc
@@ -227,6 +227,6 @@
 \contentsline {subsection}{\numberline {11.4.4}Constraints on constitutive relations for friction}{242}{subsection.1299}%
 \contentsline {section}{URLs for chapter 11}{243}{section*.1300}%
 \contentsline {chapter}{Postface for engineers, physicists, teachers}{244}{chapter*.1304}%
-\contentsline {section}{\numberline {11.5}The validity of the mathematical form of the balance laws in general relativity}{247}{section.1314}%
+\contentsline {subsection}{The validity of the mathematical form of the balance laws in general relativity}{247}{section*.1314}%
 \contentsline {section}{URLs for chapter \textit {Postface for engineers, physicists, teachers}}{248}{section*.1316}%
 \contentsline {chapter}{Bibliography}{249}{chapter*.1320}%