Thomas Gilly

Summer is fading into autumn and darkess comes sooner. Less time to spend outdoors and more for feeding the Wiki.

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The scary thing about black holes is that they are like really big subatomic particles.

• The scary thing about subatomic particles is that they're like really small black holes.

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Since the beginning of time the universe has both increased in entropy and complexity.

It occurs to me that, although it's conventional to say so, clearly this is true about entropy only in an absolute sense. The relative entropy in a statistical mechanics sense has been decreasing, as the number of states in the phase space of the universe has dramatically increased. I think. Hmm...that should have some implications...

Now I have to find out what phase space is. I tried to look it up in Wikipedia but the site seems to be down at the moment.

I think it's been down for a whole day already. Here's google's cache for Wikipedia's entry on statistical mechanics: http://216.239.57.104/search?q=cache:5jCAQggCFSQJ:en.wikipedia.org/wiki/Statistical_mechanics+site:wikipedia.org+%22statistical+mechanics%22&hl=en

Unfortunately it doesn't look like a particularly accessible definition.

All I found right off the bat was "Can Gravity Decrease Entropy?" http://math.ucr.edu/home/baez/entropy.html ...which is interesting in its own right, and has a bearing on the topic at hand.

Anyway, in short, statistical mechanics is thermodynamics as derived from information theory (and/or statistics, which is about counting, so it's the same thing); entropy can be defined in terms of the occupancy of possible states in the system (that's the phase space part).

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http://thomasgilly.com

Wow, what an unusually rich and well organized site...

Thanks, I'm an application programmer by training and I'm learning to write for the Internet.

You seem to have a broad range of interests; I like that.

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