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HNQ
2:34 AM
2
Q: Computing the metric tensor from its Killing vectors?

sylow1On page. 139 of Carroll's GR book, during the discussion of Killing vectors, he quotes an explicit coordinate basis representation for the Killing vectors on $S^2$: \begin{array}{l} R=\partial_{\phi} \\ S=\cos \phi\,\partial_{\theta}-\cot \theta \sin \phi\,\partial_{\phi} \\ T=-\sin \phi\,\partia...

 
 
16 hours later…
HNQ
6:18 PM
2
Q: How does the second law of thermodynamics function when a system is at maximum entropy?

Martin - Reinstate MonicaThe second law of thermodynamics states that the entropy in an isolated system cannot decrease This seems intuitive when considering a low entropy system transitioning to a higher entropy state, but very counterintuitive when considering a system that is currently at the greatest possible entro...

 
 
2 hours later…
HNQ
8:22 PM
4
Q: Why is Hartree-Fock considered a mean-field approach?

Karim ChahineIn studying the Hartree-Fock method for solving systems of interacting particles, I have often found that the method is referred to as a mean-field approach. Wikipedia's page for instance says that the mean-field approximation is implied. I don't see why this is the case though. In the HF method,...

 

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