I Does the Equal A Priori Probabilities Assumption Hold for Interacting Gases?

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The discussion centers on the validity of the equal a priori probabilities assumption in the microcanonical ensemble for interacting gases. It confirms that if the system is in equilibrium, all microstates remain equally probable despite particle interactions, as the Hamiltonian is conserved. The conversation also raises questions about defining equilibrium in systems with many interacting particles and the ergodic assumption, which suggests that all states are visited with equal frequency over time. Participants recommend searching for references on ergodicity in interacting systems for further insights. The importance of understanding these concepts in statistical mechanics is emphasized.
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Hi! My question has to be with the equal a priori probabilities assumption in the microcanonical ensemble when we consider an interacting system, that is, particles interacting between them but no external work or heat is done over the system. Does this assumption still hold for such a system? Thanks!
 
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Yes. If the system is in equilibrium, all microstates are equally probable, even for an interacting system.
 
So, because the interactions don't depend on time, the hamiltonian must be a conserved quantity according to Noether's theorem, and the total energy is conserved or fixed. However, I would like to know more about how to define equilibrium for a system of many interacting particles. Is there any reference to look at this closer? Also, the ergodic assumption is of interest for me, in the case of an interacting system. If you assume the equal a priori probabilities, then for very long times, all states are visited regularly with the same frecuency. Is there any reference too to see how this works? Or any attempts to prove that that hav been made?

Thank you!
 
Several references on ergodicity in interacting systems. I just typed those words in google and got may pages.
 
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