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arXiv · 2502.20400

Macroscopic quantum distinguishablity, identity and irreversibility

J. Jeknic-Dugic·M. Arsenijevic·M. Dugic
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Abstract

The basic characteristics of the classical many-particle (''macroscopic'') systems are notoriously hard to reproduce in quantum theory. In this paper we show that this is not the case for certain many-particle systems within the recently introduced theory of emergent local quantum times, the so-called, Local Time Scheme. For an isolated many-particle system consisting of large number of (approximately) isolated subsystems, distinguishability and individuality can be naturally and straightforwardly obtained. In effect, a single such many-particle system quickly evolves between the mutually approximately orthogonal states thus setting a trajectory in the state space that is not shared with any other such individual many-particle system. Irreversibility of such dynamical processes is justified for the individual systems but not for the statistical ensembles of such systems. As an application, we derive a genuine nonexponential law for decay of unstable systems, in accordance with some theoretical expectations. This, classically plausible, picture calls for detailed analysis regarding the relativistic causality and cosmological contexts.

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J. Jeknic-Dugic, M. Arsenijevic, M. Dugic. 2025-01-23. Macroscopic quantum distinguishablity, identity and irreversibility. https://arxiv.org/abs/2502.20400

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