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GAPP Seminar

GAPP Seminar

Davey 339

2024-09-10

GAPP Seminar Tuesday, Sept. 10th at 2pm in Davey 339

Speaker: George Zahariade, Jagiellonian University (Poland) Title: Semiclassical Backreaction in Quantum Mechanics

Abstract: The backreaction of quantum degrees of freedom on classical backgrounds is a poorly understood topic in theoretical physics. Most often it is treated within the semiclassical approximation with the help of various ad hoc prescriptions accounting for the effect of quantum excitations on the dynamics of the background. In this talk I will focus on two popular ones: (i) the mean-field approximation whereby quantum degrees of freedom couple to the classical background via their quantum expectation values; (ii) the stochastic method whereby the fully coupled system is evolved using classical equations of motion for various randomly sampled initial conditions of the quantum degree of freedom, and a statistical average is done a posteriori. I will evaluate the performance of each method in a simple toy model against a fully quantum mechanical treatment, identify its regime of validity, and interpret the results in terms of quantum entanglement and loss of classicality of the background.

TimeSpeakerTitle
14:00George ZahariadeSemiclassical Backreaction in Quantum Mechanics
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