Einstein for Everyone
JOHN D. NORTON
Nullarbor Press
2007
revisions 2008, 2010, 2011, 2012, 2013,
2015, 2016, 2017, 2018, 2020, 2021, 2023, 2024
This book is a continuing
work in progress. When I have time, I edit, expand and add to the
chapters. For the convenience of readers who need a stable version that
will not change, there is an archived version, which is a snapshot of
the state of the book at the date indicated:
November 7, 2023
Preface
For over two decades I have taught an introductory, undergraduate class, "Einstein for Everyone," at the University of Pittsburgh to anyone interested enough to walk through door. The course is aimed at people who have a strong sense that what Einstein did changed everything. However they do not know enough physics to understand what he did and why it was so important. The course presents just enough of Einstein's physics to give students an independent sense of what he achieved and what he did not achieve. The latter is almost as important as the former. For almost everyone with some foundational axe to grind finds a way to argue that what Einstein did vindicates their view. They certainly cannot all be right. Some independent understanding of Einstein's physics is needed to separate the real insights from the never-ending hogwash that seems to rain down on us all.
With each new offering of the course, I had the chance to find out what content worked and which of my ever so clever pedagogical inventions were failures. By this slow process of trial and error, indulging the indefinitely elastic patience of the students at the University of Pittsburgh, the course has grown to be something that works pretty well--or so it seems from my side of the lectern.
At the same time, my lecture notes have evolved. They began as chaotic pencil jottings. Over time they solidified into neater pencil script and overhead transparencies; and then into summaries that I posted on my website; and then finally those summaries were expanded into a full text that can be read independently. That text is presented here.
Its content reflects the fact that my interest lies in history and philosophy of science and that I teach in a Department of History and Philosophy of Science. There is a lot of straight exposition of Einstein's physics and the physics it inspired. However there is also a serious interest in the history of Einstein's science. A great deal of my professional life has been spent poring over Einstein's manuscripts, trying to discern how he found what he found. The results of those studies have crept in. In other places I try to show how a professional philosopher approaches deeply intractable foundational issues. The temptation in such cases is to let one's standard of rigor drop, since otherwise it seems impossible to arrive at any decision. That is exactly the wrong reaction. When the problems are intractable, we must redouble our commitment to rigor in thought; and I have tried to show how we can do this.
This
text
owes a lot to many. It came about because, years ago, the chair of the
Department of HPS, urged a meandering junior professor to teach a course
that "did" Einstein and black holes and all that stuff. The text is
indebted to the University of Pittsburgh, which has the real wisdom to
see that it gets the most from its faculty by letting them do what
fascinates them, for they will surely do that best. It owes the greatest
debt to the infinite patience of the students who have taken this class,
told me what works and what does not, and each year allowed me, at least
indirectly, to experience anew that inescapable sense of wonder when one
first grasps the beauty of what Einstein did.
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Contents
| Preface | iii |
| 1. Introduction | read |
| Special Relativity | |
| 2. Special Relativity: The Principles | read |
| 3. Special Relativity: Clocks and Rods | read |
| 4. Special Relativity: Adding Velocities | read |
| 5. Special Relativity: Relativity of Simultaneity | read |
| 6. Is Special Relativity Paradoxical? | read |
| 7. E=mc2 | read |
| 8. Origins of Special Relativity | read |
| 9. Einstein's Pathway to Special Relativity | read |
| Spacetime | |
| 10. Spacetime | read |
| 11. Spacetime and the Relativity of Simultaneity | read |
| 12. Spacetime, Tachyons, Twins and Clocks | read |
| 13. What is a Four Dimensional Space Like? | read |
| Philosophical Significance of the Special Theory of Relativity |
|
| 14. Skeptical Morals | read |
| 15. Morals About Theory and Evidence | read |
| 16. Morals about Time | read |
| 17. The Conventionality of Simultaneity | read |
| Non-Euclidean Geometry | |
| 18. Euclidean Geometry: The First Great Science | read |
| 19. Euclid's Fifth Postulate | read |
| 20. Non-Euclidean Geometry: A Sample Construction | read |
| 21.Non-Euclidean Geometry and Curved Spaces | read |
| 22. Spaces of Constant Curvature | read |
| 23. Spaces of Variable Curvature | read |
| General Relativity | |
| 24. General Relativity | read |
| 25. Gravity Near a Massive Body | read |
| 26. Einstein's Pathway to General Relativity | read |
| Cosmology and Black Holes | |
| 27. Relativistic Cosmology | read |
| 28. Time Travel Universes | read |
| 29. Our Universe: What We See | read |
| 30. Big Bang Cosmology | read |
| 31. Must There Have Been a Big Bang? | read |
| 32. Black Holes | read |
| 33. Einstein on Black Holes | read |
| 34. A Better Picture of Black Holes | read |
| Philosophical Significance of the General Theory of Relativity |
|
| 35. Geometric Morals | read |
| 36. The Ontology of Space and Time: The Relativity of Accelerated Motion | read |
| 37. The Ontology of Space and Time: The Hole Argument | read |
| 38. Theory and Evidence | read |
| 39. Cosmos and Infinity | read |
| Quantum Theory | |
| 40. Atoms and the Quanta | read |
| 41 Origins of Quantum Theory | read |
| 42. Quantum Theory of Waves and Particles | read |
| 43. A Complex Wave | read |
| 44. The Measurement Problem | read |
| 45. Time Travels with Schroedinger's Cat | read |
| 46. Einstein on the Completeness of Quantum Theory | read |
| Retrospect | |
| 47. Einstein as the Greatest of the Nineteenth Century Physicists | read |
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