Quantum Lunch: Quantum many-body fluctuations around nonlinear Schrödinger dynamics

Speaker: Chiara Boccato, UZH.

Abstract: We consider a system of bosons interacting through a two-body potential N³ᵝ⁻¹ V(Nᵝ x), scaling with the number of particles N. When a very large number of particles is involved, it is difficult to calculate physical quantities from the time-dependent Schrödinger equation. However, it is possible to approximate the dynamics by a one-particle nonlinear Schrödinger equation; the reliability of this approximation is the problem we want to investigate.
Our work focuses on fluctuations around the nonlinear Schrödinger dynamics. In a second-quantized setting, for 0 < β < 1, we construct a unitary evolution with quadratic generator, which, in the limit of large N, allows us to approximate the fully evolved state in Fock space norm.

Joint work with Serena Cenatiempo and Benjamin Schlein.