Adding decoherence to the Wigner equation
- URL: http://arxiv.org/abs/2006.01121v1
- Date: Fri, 29 May 2020 22:09:38 GMT
- Title: Adding decoherence to the Wigner equation
- Authors: Luigi Barletti, Giovanni Frosali, Elisa Giovannini
- Abstract summary: We derive a Wigner equation endowed with a decoherence term of a fairly general form.
The effect of the decoherence mechanism on the dynamics of macroscopic moments is illustrated by deriving the corresponding set of balance laws.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Starting from the detailed description of the single-collision decoherence
mechanism proposed by Adami, Hauray and Negulescu, we derive a Wigner equation
endowed with a decoherence term of a fairly general form. This equation is
shown to contain well known decoherence models, such as the
Wigner-Fokker-Planck equation, as particular cases. The effect of the
decoherence mechanism on the dynamics of the macroscopic moments (density,
current, energy) is illustrated by deriving the corresponding set of balance
laws. The issue of large-time asymptotics of our model is addressed in the
particular, although physically relevant, case of gaussian solutions. It is
shown that the addition of a Caldeira-Legget friction term provides the
asymptotic behaviour that one expects on the basis of physical considerations.
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