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The stochastic limit of quantum spin systems

L. Accardi·S. V. Kozyrev
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Abstract

The stochastic limit for the system of spins interacting with a boson field is investigated. In the finite volume an application of the stochastic golden rule shows that in the limit the dynamics of a quantum system is described by a quantum white noise equation that after taking of normal order is equivalent to quantum stochastic differential equation (QSDE). For the quantum Langevin equation the dynamics is well defined and is a quantum flow on the infinite lattice system.

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L. Accardi, S. V. Kozyrev. 1999-11-17. The stochastic limit of quantum spin systems. https://doi.org/10.1063/1.1291629

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