Writing a book on time reversal

Simulation of Book

So, I’m writing a book on the foundations of time reversal.

I’ve decided to bring back the Soul Physics blog to talk about the book as it’s being written, and maybe some other things. I’m hoping you’ll enjoy it as a little preview, and maybe even learn something about time reversal along the way. And I’m hoping to the book will benefit from the discussions in this blog’s comments.

You’ll be able to see all the posts on this topic through the Alleged Book Category.

Next time, we’ll have a little discussion about what time reversal means. But for now, here is a bare outline of what I’m planning to write about. Suggestions are welcome, and feel free to let me know in the comments if there’s something else you’d like to see.

The Curious Case of Reversal in Time: A philosophical tour of time reversal in classical and quantum physics


  1. Time reversal’s greatest hits: An overview of the great successes of the concept of time reversal in 20th century physics and philosophy, and why it’s worth learning about.
  2. How to time reversal an observable: Origins of the meaning of time reversal for measurable quantities like momentum, magnetic fields, and spin, when considered as “observables” in classical or quantum physics.
  3. How to time reverse a spacetime structure: Origins of the meaning of time reversal for spacetime structures like tensor fields, metrics, and spacetime manifolds.
  4. The joy of time reversal invariance: What we know about when a physical system is guaranteed to be temporally symmetric, and what’s special about the physical systems that enjoy this property.
  5. The simple failure of Curie’s principle: Illustration of how Curie’s principle fails for time reversal, and a discussion of possible replacements.
  6. T-violation and the origin of time asymmetry: A classification of the known ways of testing for time asymmetry (aka T-violation) in physical systems. This chapter is related to a talk I gave in April 2013 at the Penn State Institution for Gravitational Physics and Geometry; you can see the slides here.
  7. T-violation beyond the standard model: A discussion of the extent to which our evidence for T-violation extends to theories that go beyond the standard model of particle physics.
  8. CPT-reversal: What CPT means, what’s important about it, and in particular whether it allows us to think of antiparticles as “regular particles moving backwards in time” as was suggested by Feynman.
  9. The CPT Theorem and Beyond: The various statements of the CPT theorem, their significance, and the extent to which CPT invariance may fail in future physical theories.
  10. Time reversal, antimatter, and the cosmos: The relationship between time reversal, CPT, and some puzzles of modern cosmology.

6 thoughts on “Writing a book on time reversal

  1. Bryan Post author

    Thanks guys. Writing a lot of this book in Los Angeles over the summer, arriving in London in October. Hope to be through with a good portion before then, and look forward to hearing your comments.

  2. Captain Cosmic

    I would recommend Robert Sachs 1987 monograph : The Physics of Time Reversal, The University of Chicago Press, ISBN 0-226-73331-9 (paperback), as a good reference to your new book. It has a particular emphasis on Quantum Mechanical systems.