posted by anonymous .
The entropy of a system is a measure of that system's disorder. Why is it appropriate to describe a laser as an entropy-reducing device?
I take some issue with the first sentence. It is better, in my view, to describe entropy as a measure of chaos. As chaos in a system increases, the entropy is a measure of that. If the chaos decreases, entropy decreases. Now in a laser, what is happening to the molecules in the laser as it lases? Is it becoming more chaotic, or not?