Monday, March 30, 2009

The Physics of Maxwell's Demon and Information

Maxwell's Demon has been a rather popular topic, both within the circle of legitimate scientific research and, at the other end, among crackpots (no surprise there). For those not familiar with Maxwell's Demon thought experiment, there are many cites that do a very good job at explaining what it is (see here and here).

There is a very good (and lengthy) review of the physics of Maxwell's Demon in the current issue of Rev. Mod. Phys.[1]

Abstract: Maxwell's demon was born in 1867 and still thrives in modern physics. He plays important roles in clarifying the connections between two theories: thermodynamics and information. Here the history of the demon and a variety of interesting consequences of the second law of thermodynamics are presented, mainly in quantum mechanics, but also in the theory of gravity. Also highlighted are some of the recent work that explores the role of information, illuminated by Maxwell's demon, in the arena of quantum-information theory.

The history in itself is fascinating and worth reading.


[1] K. Maruyama et al., Rev. Mod. Phys. v.81, p.1 (2009), or you can get the ArXiv version here.

1 comment:

R said...

There was a short article on Science ( about the experimental realization of Maxwell's demon.

After some clicking, I found out that the group (I really didn't keep looking for another one) that did it is at UT Austin. ( There seems to be a new version of it up now. I haven't read this paper, but the Science one is very interesting.

Anyways, just thought making an experimental demon was kinda cool.