# Preservation of quantum coherence under Lorentz boost for narrow uncertainty wave packets

## TL;DR

This paper investigates how relativistic boosts affect quantum coherence in single-particle Gaussian wave packets, showing that coherence generally decays but can be preserved in narrow uncertainty states under large boosts.

## Contribution

It demonstrates that quantum coherence can be maintained under Lorentz boosts for narrow wave packets, providing a basis-independent analysis and practical examples with neutron wave functions.

## Key findings

- Coherence decays with increased momentum and boost.
- Narrow uncertainty wave packets can preserve coherence under large boosts.
- Quantitative analysis with neutron wave functions supports the theoretical results.

## Abstract

We consider the effect of relativistic boosts on single particle Gaussian wave packets. The coherence of the wave function as measured by the boosted observer is studied as a function of the momentum and the boost parameter. Using various formulations of coherence it is shown that in general the coherence decays with the increase of the momentum of the state, as well as the boost applied to it. Employing a basis-independent formulation, we show however, that coherence may be preserved even for large boosts applied on narrow uncertainty wave packets. Our result is exemplified quantitatively for practically realizable neutron wave functions.