Fixing semi-classical physics from first principles: how to derive effective classical-quantum dynamics from open quantum theory
Quantum Physics
2026-04-10 v1
Abstract
Semi-classical approaches approximate fully quantum descriptions with partially classical ones. Here we use a toy model to highlight the failings of the standard mean-field semi-classical approach, and show how including environmental decoherence can lead to improved semi-classical theories that are exact descriptions of the original quantum dynamics. In doing so, we show how consistent models of classical-quantum dynamics can arise as effective descriptions of open quantum systems.
Cite
@article{arxiv.2604.08024,
title = {Fixing semi-classical physics from first principles: how to derive effective classical-quantum dynamics from open quantum theory},
author = {Isaac Layton},
journal= {arXiv preprint arXiv:2604.08024},
year = {2026}
}
Comments
Talk given at Concepts of Quantum and Spacetime, KEK, March 2026