English

Norm approximation for the Fr\"ohlich dynamics in the mean-field regime

Mathematical Physics 2022-07-05 v1 math.MP

Abstract

We study the time evolution of the Fr\"ohlich Hamiltonian in a mean-field limit in which many particles weakly couple to the quantized phonon field. Assuming that the particles are initially in a Bose-Einstein condensate and that the excitations of the phonon field are initially in a coherent state we provide an effective dynamics which approximates the time evolved many-body state in norm, provided that the number of particles is large. The approximation is given by a product state which evolves according to the Landau-Pekar equations and which is corrected by a Bogoliubov dynamics. In addition, we extend the results from [Arch. Ration. Mech. Anal. 240, 383-417 (2021)] about the approximation of the time evolved many-body state in trace-norm topology to a larger class of many-body initial states with an improved rate of convergence.

Keywords

Cite

@article{arxiv.2207.01598,
  title  = {Norm approximation for the Fr\"ohlich dynamics in the mean-field regime},
  author = {Nikolai Leopold},
  journal= {arXiv preprint arXiv:2207.01598},
  year   = {2022}
}