Prove the 3 definitions of entropy are equivalent (stat. mechanics)

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Tosh5457
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Homework Statement



[tex] S(E,V) = kln(\Gamma(E) )\\<br /> S(E,V) = kln(\omega(E) )\\<br /> S(E,V) = kln(\Sigma(E) )\\[/tex]

S entropy, k Boltzmann's constant. Prove these 3 are equivalent up to an additive constant.

Homework Equations



[tex] \Gamma(E) = \int_{E<H<E+\Delta}^{'}dpdq\\<br /> \Gamma(E)=\omega\Delta \\<br /> \Delta << E\\<br /> <br /> \Sigma(E) = \int_{H<E}^{'}dpdq\\<br /> \omega = \frac{\partial \Sigma}{\partial E}\\[/tex]

H is the system's Hamiltonian and E is an arbitrary energy. These are integrations over all the p and q's, I wrote them like that to abbreviate.

The Attempt at a Solution



Using the 1st definition I can get to the 2nd one, but I can't reach at sigma's definition.
[tex] <br /> kln(\Gamma(E)) = kln(\omega\Delta) = kln(\omega) + kln(\Delta)\\<br /> ln(\Delta) << ln(\omega) => S = kln(\omega)\\[/tex]
 
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I would say ##\Gamma (E)=\Sigma (E+\Delta) -\Sigma (E)=\Delta \frac{\partial \Sigma}{\partial E}+...##