Gluon Entanglement Entropy inside a Nucleon: A Toy Model

TL;DR

This paper introduces a simplified model of a nucleon with static quarks and SU(3) gauge interactions, analyzing gauge field entanglement and its evolution after a quench.

Contribution

It presents a toy model capturing key features of nucleon structure and studies gauge entanglement entropy dynamics post-quench.

Findings

Entanglement entropy reflects salient nucleon features.

Post-quench entropy is dominated by dynamical contributions.

The model reproduces key aspects of physical nucleon states.

Abstract

We construct a toy model of a nucleon, in which three static quarks interact via a SU(3) gauge field on a planar honeycomb lattice. The dynamics of the gauge field is described by the Kogut-Susskind Hamiltonian, truncated to the lowest three SU(3) irreducible representations. We show that the internal structure of the toy nucleon reflects salient features of the physical nucleon state. We then find the entanglement entropy of the gauge field within the nucleon state and compute its time evolution after a quench, in which all three valence quarks are suddenly removed. We show that the entanglement entropy in the final state is dominated by the dynamically generated contribution rather than the initial state entropy.