Physics from Symmetry

What Hacker News says

1. particleguyJan 2025
   Yes, Quantum Field Theory can be explained through Lie groups. SU(2) is isomorphic to the quaternions of norm 1, and SU(2) is important if you want to understand the Lorentz group and Poincare group, which represent the symmetries of spacetime and special relativity. Check out the text book Physics From Symmetry by Jakob Schwichtenberg if you would like an approach that derives modern physics primarily from algebra
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2. teleforceOct 2022
   This is an excellent book on the subject by Jakob Schwichtenberg [1].

   [1]Physics From Symmetry:

   http://physicsfromsymmetry.com/

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3. wrycoderMay 2021
   I'd recommend

   Physics From Symmetry by Jakob Schwichtenberg

   Also, (though I've not read it) this appears to be a longer, more detailed text in the same vein:

   Quantum Theory, Groups and Representations: An Introduction by Peter Woit

   This one gets to the EM field on page 573 :-/

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4. particleguyDec 2019
   I like Physics from Symmetry by Jakob Schwichtenberg as an explanation of how spin arises from a modern understanding of physics. The book was written while the author was a Masters student, and so it is much closer to the way an undergrad physics student would explain it to another student. The author is willing to skip details in favor of more general understanding.

   The way the book will describe it is from the perspective of group theory. If you assume that the laws of nature in a relativistic flat spacetime do not change under rotations, translations (in both space and time), and boosts (transformation between frames of reference of constant velocity), then these transformations define a Lie group called the Poincaré group. Representation theory then says that the representations of the Poincare group are characterized by two numbers. These two numbers are identified as a nonnegative mass and a spin. One interpretation is that these representations are indeed what "particles" are in Quantum Field Theory.

   https://en.wikipedia.org/wiki/Wigner%27s_classification

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5. wrycoderMar 2019
   http://nbodyphysics.com/blog/2017/06/12/on-being-the-dumbest...

   Somehow I doubt it! In any case, you are like me - doing engineering and software, while doing my physics as a hobby and loving it. I'm working on Physics from Symmetry. Definitely a 21st century book - not at all like the traditional development of the subject.

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6. dustingetzFeb 2024
   also Physics from Symmetry spends 1/3 the book on lie theory passing through quaternions

   https://www.amazon.com/Physics-Symmetry-Undergraduate-Lectur...

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