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### Quantum Theory, Groups and Representations

### Not Even Wrong: The Book

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# Category Archives: Favorite Old Posts

## The NSA, NIST and the AMS, Part II

Last summer I wrote here about an article in the AMS Notices which appeared to make misleading claims about the NSA’s involvement in putting a backdoor in an NIST cryptography standard known as DUAL_EC_DRBG. The article by Richard George, a … Continue reading

Posted in Favorite Old Posts, Uncategorized
23 Comments

## Use the Moment Map, not Noether’s Theorem

For a fourth provocative slogan about quantum mechanics I’ve chosen: Use the moment map, not Noether’s Theorem. Pretty much every physics textbook these days explains the way symmetry principles work as: Start with an action functional, invariant under a Lie … Continue reading

Posted in Favorite Old Posts, Quantum Mechanics
25 Comments

## Nature is Fundamentally Conformally Invariant

For a third slogan I’ve chosen: Nature is fundamentally conformally invariant. Note the weasel-word “fundamentally”. We know that nature is not conformally invariant, but the kind of thing I have in mind is pure QCD, where the underlying classical theory … Continue reading

Posted in Favorite Old Posts, Quantum Mechanics
33 Comments

## Grand Unification of Mathematics and Physics

For a second slogan about quantum mechanics I’ve chosen: Quantum mechanics is evidence of a grand unification of mathematics and physics. I’m not sure whether this slogan is likely to annoy physicists or mathematicians more, but in any case Edward … Continue reading

Posted in Favorite Old Posts, Quantum Mechanics, Uncategorized
7 Comments

## Quantum Theory is Representation Theory

For a first slogan (see here for slogan zero) I’ve chosen: Quantum theory is representation theory. One aspect of what I’m referring to is explained in detail in chapter 14 of these notes. Whenever you have a classical phase space … Continue reading

Posted in Favorite Old Posts, Quantum Mechanics
43 Comments

## What’s Hard to Understand is Classical Mechanics, Not Quantum Mechanics

For a zeroth slogan about quantum mechanics, I’ve chosen What’s hard to understand is classical mechanics, not quantum mechanics. The slogan is labeled by zero because it’s preliminary to what I’ve been writing about here. It explains why I don’t … Continue reading

Posted in Favorite Old Posts, Quantum Mechanics
46 Comments

## String Theory and Post-Empiricism

Note: This is being published simultaneously here and at Scientia Salon. Discussion will be at the Scientia Salon site. Last month’s Strings 2014 conference in Princeton included two remarkable talks by prominent physicists, both of whom invoked philosophy in a … Continue reading

Posted in Favorite Old Posts, Uncategorized
Comments Off on String Theory and Post-Empiricism

## Ten Years of Not Even Wrong

This blog was started a little bit over ten years ago, and I’ve been intending for a while to write something marking the occasion and commenting on what has changed over the past ten years. I’ve found this mostly a … Continue reading

Posted in Favorite Old Posts, Uncategorized
62 Comments

## Particle Fever

Yesterday I got a chance to see Particle Fever, the long-awaited film about particle physics. It’s at the New York Film Festival, where there will be another showing on Wednesday, although tickets are already sold out. Oliver Peters was also … Continue reading

Posted in Favorite Old Posts, Multiverse Mania, Uncategorized
20 Comments

## Hard Evidence for the Multiverse Found, but String Theory Limits the Space Brain Threat

In recent years there have been many claims made for “evidence” of a multiverse, supposedly found in the CMB data (see for example here). Such claims often came with the remark that the Planck CMB data would convincingly decide the … Continue reading