
#19
Dec1412, 10:24 AM

P: 835

In Penrose's book the Road to Reality, he sort of asserted without proof that when gravity pulls things together, this increases the entropy. It seems that if this is to be the case, gravity must somehow increase the degrees of freedom of the system, but this wasn't explained.




#20
Dec1412, 10:52 AM

P: 5,462

There is not complete overlap between the domains of applicability of thermodynamics and statistical mechanics. They both deal with areas not covered by the other. 



#21
Dec1412, 10:55 AM

P: 166

My understanding is that as gravity pulls disorganized masses together into objects like stars and planets, the entropy of that particular system decreases, but that this is offset by the rise in entropy over a wider scale / bigger system. As with most of these things, I suppose it depends on how wide you want to cast your net when defining the boundaries of the system.
A house of cards on its own is a low entropy arrangement, but the entropy of the system has increased overall if you include the energy used by the person building it. 



#22
Dec3112, 12:37 AM

P: 2




Register to reply 
Related Discussions  
Physical interpretation of entropy if expansion causes a state of maximum entropy?  Cosmology  17  
The entropy of the universe? (attempts to define gravitational entropy)  Cosmology  22  
Show how the Boltzmann entropy is derived from the Gibbs entropy for equilibrium  Advanced Physics Homework  4  
How is the entropy of the universe increasing when entropy is simply transferred?  Introductory Physics Homework  5  
String entropy and black hole entropy  Beyond the Standard Model  3 