Fundamental assumptions of statistical mechanics

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The fundamental assumption of statistical mechanics posits that all micro-states are equally probable, forming the basis for theories on entropy and various distributions. This assumption emerged from historical scientific practices, as it consistently yielded successful predictions and explanations in thermodynamics. Despite initial skepticism about its validity, the assumption has proven effective in modeling physical systems. The notion that some states might seem more likely than others challenges this premise, yet the equal probability of states remains a cornerstone of statistical mechanics. Overall, the assumption's utility and consistency in results reinforce its importance in the field.
Mayan Fung
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The assumption states that all states (or I shall say micro-states) are equally probable. This is the foundation where we construct our theories on entropy, different kind of distributions, etc.
Is there any explanation for this assumption? Or why did the scientists that time take this assumption? I mean what made them think this is so fundamental.
 
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Perhaps the best reason for it is they found that it works. It's kind of an odd assumption, (IMO=in my opinion), and my instincts, perhaps yours also, would tell you that some states seemingly would be more likely to occur than others. It surprised me a little when I first learned the subject, and you are correct, that the entire subject is based on the premise of all states of the same energy being equally probable.
 

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