The Current State of Coherent States

TL;DR

This paper reviews the evolving definitions and properties of coherent states, highlighting recent developments that expand their applicability to various dynamical systems like the hydrogen atom.

Contribution

It surveys current trends in coherent state definitions, emphasizing the removal of group connections and the resulting broader applicability.

Findings

Recent definitions allow coherent states for diverse systems.

Temporal stability achieved without group connections.

Broader applicability to systems like the hydrogen atom.

Abstract

The original canonical coherent states could be defined in several ways. As applications for other sets of coherent states arose, the rules of definition were correspondingly changed. Among such rule changes were a change of group and relaxation of the analytic nature of the labels. Recent developments have done away with the group connections altogether and thereby allowed sets of coherent states to be defined that are temporally stable for a wide variety of dynamical systems including the hydrogen atom. This article outlines some of the current trends in the definitions and properties of present-day coherent states.