Quantum systems with time-dependent boundaries

TL;DR

This paper discusses the behavior of quantum particles in systems where the boundaries of their confinement change over time, demonstrating that such dynamics preserve unitarity and do not cause decoherence.

Contribution

It provides a detailed analysis of quantum systems with moving boundaries, highlighting that unitarity is maintained and decoherence is avoided during boundary changes.

Findings

Unitarity is preserved during boundary movements.

Changing boundaries do not induce decoherence.

The analysis applies to non-relativistic particles in bounded domains.

Abstract

We present here a set of lecture notes on quantum systems with time-dependent boundaries. In particular, we analyze the dynamics of a non-relativistic particle in a bounded domain of physical space, when the boundaries are moving or changing. In all cases, unitarity is preserved and the change of boundaries does not introduce any decoherence in the system.