Entanglement generation in $(1+1)D$ QED scattering processes

TL;DR

This paper investigates real-time meson-meson scattering in (1+1)D QED using Tensor Networks, revealing how entanglement and scattering amplitudes vary with interaction strength and initial conditions.

Contribution

It introduces a tensor network approach to simulate meson scattering in (1+1)D QED and uncovers a threshold behavior in entanglement growth.

Findings

Entanglement growth accelerates past a certain coupling threshold.

Scattering amplitudes are computed for elastic collisions.

Rich phenomenology observed in meson interactions across coupling regimes.

Abstract

We study real-time meson-meson scattering processes in $(1+1)$-dimensional QED by means of Tensor Networks. We prepare initial meson wave packets with given momentum and position introducing an approximation based on the free fermions model. Then, we compute the dynamics of two initially separated colliding mesons, observing a rich phenomenology as the interaction strength and the initial states are varied in the weak and intermediate coupling regimes. Finally, we consider elastic collisions and measure some scattering amplitudes as well as the entanglement generated by the process. Remarkably, we identify two different regimes for the asymptotic entanglement between the outgoing mesons: it is perturbatively small below a threshold coupling, past which its growth as a function of the coupling abruptly accelerates.