Quantum simulation of baryon scattering in SU(2) lattice gauge theory

TL;DR

This paper demonstrates real-time quantum simulations of baryon scattering in a 1+1D SU(2) lattice gauge theory, revealing elastic and entanglement phenomena across different baryon number sectors.

Contribution

It introduces tensor-network techniques for simulating real-time hadronic scattering in SU(2) lattice gauge theory, highlighting new entanglement effects in the mixed baryon sector.

Findings

Strong coupling channels show elastic scattering similar to the Schwinger model.

Mixed baryon sector exhibits entanglement and delocalization during collisions.

Local observables and entanglement entropy characterize the scattering processes.

Abstract

We present a first real-time study of hadronic scattering in a $(1+1)$-dimensional SU(2) lattice gauge theory with fundamental fermions using tensor-network techniques. Working in the gaugeless Hamiltonian formulation, we investigate scattering processes across sectors of fixed global baryon number $B = 0, 1, 2$, corresponding respectively to meson--meson, meson--baryon, and baryon--baryon collisions. At strong coupling, the $B = 0$ and $B = 2$ channels exhibit predominantly elastic dynamics closely resembling the U(1) Schwinger model. The mixed $B = 1$ sector displays qualitatively new behavior: meson and baryon wavepackets become entangled during the collision, with the slower state becoming spatially delocalized while the faster one propagates ballistically. We characterize these processes through local observables, entanglement entropy, and the information lattice.