Entangled Scent of a Charge

TL;DR

This paper explores how charged particles induce an entangled, dressed ground state in quantum field theory, leaving a persistent electromagnetic imprint that challenges classical notions of charge effects.

Contribution

It introduces a detailed analysis of the entanglement and dressing of the quantum vacuum caused by moving charges, extending infrared field theory insights to new contexts.

Findings

Charged particles create an entangled vacuum state involving soft photons.

The electromagnetic effect of a charge persists indefinitely, unlike classical predictions.

Results suggest nonlocal information in quantum fields may escape black hole horizons.

Abstract

We argue that the ground state of a field theory, in the presence of charged particles, becomes an entangled state involving an infinity of soft photons. The quantum field vacuum is altered by the passage of a uniformly moving charge, leaving in its wake a different dressed ground state. In this sense a charged particle leaves its electromagnetic scent even after passing by. Unlike in classical electrodynamics the effect of the charge remains even at infinite time. The calculation is done in detail for the ground state of a spacetime wedge, although the results are more general. This agrees in spirit with recent results over the infrared aspects of field theory, although the technical details are different. These considerations open the possibility that the information carried by quantum fields, being nonlocal, does not disappear beyond the horizon of black holes.