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arXiv · 1904.04950

Universal density matrix for the phase space

E. E. Perepelkin·B. I. Sadovnikov·N. G. Inozemtseva·E. V. Burlakov
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Abstract

In this paper, a new representation of the Wigner function for a quantum system in the phase space is proposed. The new representation is of the form $W=\operatorname{Sp}\left[ \rho \mathcal{W} \right]$, where $\rho$ is the density matrix, and $\mathcal{W}$ is the universal density matrix. The density matrix $\rho$ for each quantum system is different, and the universal matrix $\mathcal{W}$ is the same for any quantum system. Thus, the matrix $\mathcal{W}$ has a fundamental character. In the work, the elements of the universal matrix $\mathcal{W}$ were found explicitly and their properties were investigated. The diagonal elements of the matrix $\mathcal{W}$ are the Wigner functions of the harmonic oscillator, which do not introduce dissipation into the quantum system. The off-diagonal elements of the matrix $\mathcal{W}$ contain frequency oscillations responsible for dissipations in the quantum systems.

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E. E. Perepelkin, B. I. Sadovnikov, N. G. Inozemtseva, E. V. Burlakov. 2019-04-10. Universal density matrix for the phase space. https://arxiv.org/abs/1904.04950

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