# Electromagnetic fields from quantum sources in heavy-ion collisions

## TL;DR

This paper calculates the electromagnetic fields generated by quantum particles in heavy-ion collisions, revealing significant differences from classical fields due to quantum diffusion effects, emphasizing the need for quantum treatment of valence quarks.

## Contribution

It provides a quantum-mechanical computation of electromagnetic fields from relativistic particles, highlighting differences from classical Coulomb fields in heavy-ion collision scenarios.

## Key findings

- Quantum fields differ in magnitude and direction from classical Coulomb fields.
- Quantum diffusion effects are significant in electromagnetic field calculations.
- Full quantum treatment is necessary for accurate modeling of heavy-ion collision environments.

## Abstract

We compute the electromagnetic field created by an ultrarelativistic charged particle in vacuum at distances comparable to the particle Compton wavelength. The wave function of the particle is governed by the Klein-Gordon equation, for a scalar particle, or the Dirac equation, for a spin-half particle. The produced electromagnetic field is essentially different in magnitude and direction from the Coulomb field, induced by a classical point charge, due to the quantum diffusion effect. Thus, a realistic computation of the electromagnetic field produced in heavy-ion collisions must be based upon the full quantum treatment of the valence quarks.