In looking at phonons, and their energy, I came across the Partition function. THis was needed to calculate the internal energy of the solid.(adsbygoogle = window.adsbygoogle || []).push({});

But howcome the Partition fucntion is used, and not the GRAND Partition function? The number of phonons is not conserved, I know that, but isn't N, the number, fixed in the Partition function??? Surely one should used the GPF to take into acount the varying number??

I guess I have misunderstood something here. Any help appreciated!!

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# Partition Function for Phonons

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