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arXiv · 2110.00458

Bogoliubov Dynamics and Higher-order Corrections for the Regularized Nelson Model

Marco Falconi·Nikolai Leopold·David Mitrouskas·Sören Petrat
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Abstract

We study the time evolution of the Nelson model in a mean-field limit in which N non-relativistic bosons weakly couple (w.r.t. the particle number) to a positive or zero mass quantized scalar field. Our main result is the derivation of the Bogoliubov dynamics and higher-order corrections. More precisely, we prove the convergence of the approximate wave function to the many-body wave function in norm, with a convergence rate proportional to the number of corrections taken into account in the approximation. We prove an analogous result for the unitary propagator. As an application, we derive a simple system of PDEs describing the time evolution of the first- and second-order approximation to the one-particle reduced density matrices of the particles and the quantum field, respectively.

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Marco Falconi, Nikolai Leopold, David Mitrouskas, Sören Petrat. 2021-10-01. Bogoliubov Dynamics and Higher-order Corrections for the Regularized Nelson Model. https://doi.org/10.1142/s0129055x2350006x

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