Re: [math-fun] Stupid physics question

On 7/17/06, Henry Baker <hbaker1@pipeline.com> wrote:

According to Noether, energy conservation is equivalent to time-invariance & other conservation laws are equivalent to other symmetries.

So here's the question:

the laws of physics, as we currently understand them, imply that _information_ is conserved -- we can run physics movies backwards, so long as enough (i.e., _all_) detail is retained. This appears to be the case even in the face of black holes and quantum spookiness.

So what is the corresponding symmetry?

You already named it: reversibility http://finitenature.com/reversibility/index.html -- Mike Stay metaweta@gmail.com http://math.ucr.edu/~mike