Quantum Features of Macroscopic Fields: Entropy and Dynamics
AbstractMacroscopic fields such as electromagnetic, magnetohydrodynamic, acoustic or gravitational waves are usually described by classical wave equations with possible additional damping terms and coherent sources. The aim of this paper is to develop a complete macroscopic formalism including random/thermal sources, dissipation and random scattering of waves by environment. The proposed reduced state of the field combines averaged field with the two-point correlation function called single-particle density matrix. The evolution equation for the reduced state of the field is obtained by reduction of the generalized quasi-free dynamical semigroups describing irreversible evolution of bosonic quantum field and the definition of entropy for the reduced state of the field follows from the von Neumann entropy of quantum field states. The presented formalism can be applied, for example, to superradiance phenomena and allows unifying the Mueller and Jones calculi in polarization optics. View Full-Text
Share & Cite This Article
Alicki, R. Quantum Features of Macroscopic Fields: Entropy and Dynamics. Entropy 2019, 21, 705.
Alicki R. Quantum Features of Macroscopic Fields: Entropy and Dynamics. Entropy. 2019; 21(7):705.Chicago/Turabian Style
Alicki, Robert. 2019. "Quantum Features of Macroscopic Fields: Entropy and Dynamics." Entropy 21, no. 7: 705.
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.