What is the meaning of non-degenerate in statistical mechanics?

[ck00]

why do we say that a classically behaved gas is non-degenerate and a quantum behaved gas is degenerate?
I can't get why the word of "degeneracy" here can distinguish two kinds of behavior of gas.

 

[ck00]

does anyone know it?

 

[nucl34rgg]

http://farside.ph.utexas.edu/teaching/qmech/lectures/node65.html

This website is a great resource for physics students (like me). Here, he basically shows that we call matter "degenerate" if the Pauli Exclusion Principle is the main source of the pressure of the matter. Two identical fermions, such as electrons, can't be in the same quantum state at the same time. If this resistance to being in the same state is the main thing keeping the electrons apart, then the electron gas is behaving like a degenerate gas.

 

[Y2H]

I completely disagree with nucl34rgg btw since a gas of bosons (which obviously doesn’t fallow the Pauli exclusion principle) can be degenerate. I advise you to check out the Degenerate Matter page on Wikipedia.

 

[Jorriss]

There's a wikipedia page on this.
http://en.wikipedia.org/wiki/Degenerate_matter