Ehrenfest’s Theorem revisited

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Henryk Stanisław Arodź

Abstract

Historically, Ehrenfest’s theorem (1927) is the first one which shows that classical physics can emerge from quantum physics as a kind of approximation. We recall the theorem in its original form, and we highlight its generalizations to the relativistic Dirac particle and to a particle with spin and izospin. We argue that apparent classicality of the macroscopic world can probably be explained within the framework of standard quantum mechanics.

Article Details

Section
Emergence of the Classical

References

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