Equipartition Theorem: Hamiltonian Form & Canonical Transformations

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The discussion centers on the equipartition theorem in relation to a specific Hamiltonian expressed as a sum of squares of coordinates and momenta. Participants explore whether there are Hamiltonians that do not conform to this square form but can still lead to the same conclusions through canonical transformations. The meaning of the equipartition theorem being "correct" is questioned, particularly in terms of energy distribution across degrees of freedom. The integrability and separability of the Hamiltonian are also discussed, raising concerns about the validity of ensemble averages in non-ergodic systems. Ultimately, the conversation highlights the relationship between Hamiltonians and the conditions under which the equipartition theorem applies.
Petar Mali
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I have one question. If I have Hamiltonian:

H=\sum^{f_1}_{i=1}\alpha_iq_i^2+\sum^{f_2}_{i=1}\beta_ip_i^2

I can show that for the Hamiltonian of this type equipartition theorem is correct. Is there any Hamiltonian which is not a function od squares of coordinates and impulses are from which I can get this Hamiltonian some using canonical transformation. Example perhaps?
 
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What does it mean "equipartition theorem is correct" ?
I think the hamiltonian is both integrable and separable, since it's not ergodic does the ensemble averages have sense?

Ll.
 
You can prove that every degree of fredom have the same energy - equipartition theorem only for the Hamiltonian

<br /> H=\sum^{f_1}_{i=1}\alpha_iq_i^2+\sum^{f_2}_{i=1}\beta_ip_i^2<br />

or maybe the Hamiltonian which canonical transformation is


<br /> H=\sum^{f_1}_{i=1}\alpha_iq_i^2+\sum^{f_2}_{i=1}\beta_ip_i^2<br />

I think that ''
mysterious '' Hamiltonian have the same form as one as I wrote! So for example


<br /> K=\sum^{F_1}_{i=1}\alpha_iQ_i^2+\sum^{F_2}_{i=1}\beta_iP_i^2<br />

Am I right?
 
Hello! Let's say I have a cavity resonant at 10 GHz with a Q factor of 1000. Given the Lorentzian shape of the cavity, I can also drive the cavity at, say 100 MHz. Of course the response will be very very weak, but non-zero given that the Loretzian shape never really reaches zero. I am trying to understand how are the magnetic and electric field distributions of the field at 100 MHz relative to the ones at 10 GHz? In particular, if inside the cavity I have some structure, such as 2 plates...
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