Action for classical, quantum, closed and open systems

2023/07/23 by Polonyi, Janos
#FOS: Physical sciences #High Energy Physics - Theory (hep-th) #Quantum Physics (quant-ph)

paper · doi:10.48550/arxiv.2307.12320

Abstract

It is well known that the action functional can be used to define classical, quantum, closed, and open dynamics in a generalization of the variational principle and in the path integral formalism in classical and quantum dynamics, respectively. These schemes are based on an unusual feature, a formal redoubling of the degrees of freedom. Several arguments to motivate the redoubling are put forward in classical and quantum mechanics to demonstrate that such a formalism is natural.

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