Physics of Particles and Nuclei

Kinematic Properties of a Quantum System in Phase Space

E. E. Perepelkin, Б. И. Садовников, Наталья Германовна Иноземцева, P. V. Afonin, Полякова Римма Васильевна, M. B. Sadovnikova

Published May 25, 2026• 0 citations

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Abstract

The paper describes the kinematic properties of quantum systems in terms of phase space. Despite the Heisenberg uncertainty principle, the consideration of quantum systems in phase space is widely used with the apparatus of quasi-probability density functions, such as the Wigner function and the gauge-invariant Weyl–Stratonovich function. The term “quasi-density” refers to the presence of phase-space regions with negative values of the probability density function and arouses interest in possible physical interpretations of such values. The kinematic properties of the systems are considered within the Wigner–Vlasov formalism, which enables to link the classical and quantum descriptions through a unified mathematical apparatus using the distribution function in phase space.

DOI: 10.1134/s1063779625701564

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