🚀 go-pugleaf

In article <23767@galaxy.ucr.edu> baez@ucrmath.ucr.edu (john baez) writes:

> In solid state you have
> quite a bit of choice in terms of finding systems that have roughly some
> Lagrangian or other, so you can really test your mathematical notions to
> some extent.  (Typically, of course, the real condensed matter system is
> more complicated than the Lagrangian you guessed for it, so these "tests"
> are always suspect.)

Oh, but that's the whole point of a renormalization group analysis,
right?  You just show your Lagrangian includes all of the relevant
parameters.

In a sense, I think that the renormalization group justifies, in
retrospect, a lot of what physicists have done for over a century:
modeling a very complicated system by a simple mathematical
description.
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Matthew Austern                   Just keep yelling until you attract a
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