Entanglement structure of quantum fields through local probes

TL;DR

This paper introduces a new framework using local probes to analyze the entanglement structure of quantum fields, avoiding UV divergences and clarifying the limits of entanglement harvesting between spacetime regions.

Contribution

It proposes a novel, divergence-free method to study entanglement in quantum field theory using particle detector formalism, enhancing understanding of entanglement distribution in spacetime.

Findings

Framework captures entanglement between arbitrary spacetime regions

Establishes limits on entanglement harvesting efficiency

Motivates operational definition of spacetime subregion entanglement

Abstract

We present a framework to study the entanglement structure of a quantum field theory inspired by the formalism of particle detectors in relativistic quantum information. This framework can in principle be used to faithfully capture entanglement in a QFT between arbitrary-shaped regions of spacetime without encountering UV divergences, bypassing many of the issues typically present in other approaches. Our results also establish the limits of the efficiency of entanglement harvesting, and may also be used to motivate an operational definition of entanglement between spacetime subregions in field theory.