Doug Natelson, writes one of the few blogs on condensed matter physics. He recently wrote a blog on What is temperature? I don't really like his perspective. I think it is best to define temperature in macroscopic and operational terms, using the zeroth law of thermodynamics. The attached slides are from my undergraduate lectures. The key ideas are
* the zeroth law allows us to assign a single number to a thermodynamic system that has the important property that this number will tell us whether or not the system will change when it is brought into thermal contact with another system.
* a thermometer is just a thermodynamic system with just one state variable.
Subscribe to:
Post Comments (Atom)
Emergence and quantum theories of gravity
Einstein’s theory of General Relativity successfully describes gravity and large scales of length and mass. In contrast, quantum theory desc...

-
Is it something to do with breakdown of the Born-Oppenheimer approximation? In molecular spectroscopy you occasionally hear this term thro...
-
I welcome discussion on this point. I don't think it is as sensitive or as important a topic as the author order on papers. With rega...
-
Nitrogen fluoride (NF) seems like a very simple molecule and you would think it would very well understood, particularly as it is small enou...
Adkins' "Equilibrium Thermodynamics" (http://www.amazon.com/Equilibrium-Thermodynamics-C-J-Adkins/dp/0521274567) has a discussion of this view of temperature that I like very much. It is a little dry and formal but also quite rigorous. That said you need some mathematical and physical sophistication to fully appreciate what's going on. I got a lot more out of this book when I first prepared to teach undergrad thermodynamics than when I read it as an undergrad!
ReplyDelete