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HNQ
4:13 AM
3
Q: Earth rotation: What provides the energy?

FernandoWe all know the earth is rotating around its own axis. From a physics energy point of view, some thing has to provide energy for the rotation. What provides the energy to rotate?

 
 
12 hours later…
HNQ
3:50 PM
3
Q: Are integers unphysical/unnatural?

Vlad SamoilovWhen I first looked into number theory, I was surprised about why mathematicians are so obsessed about integers, primes and so on. As far as I understand, (almost) all integers in the real world arise as an approximate description of composite dynamics. I think anyone here understands why individ...

 
 
1 hour later…
HNQ
5:05 PM
1
Q: The Functional Determinants in Peskin and Schroeder (Eq.9.77)

skyI'm working on the Eq.9.77 in Peskin (page 304) However, I test the identity and find it doesnʻs work. For $B=\{\{3, -2, 4\}, \{-2, 6, 2\}, \{4, 2, 3\}\}$, The left-hand side of the Eq.(9.77) is -98, and the right is 54. Why does this happen? What are the conditions for this identity to be true...

 

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