English

The quantum harmonic oscillator on a circle -- fragmentation of the algebraic method

Quantum Physics 2026-03-26 v1

Abstract

A quantum particle on a circle in a quadratic potential exhibits a spectrum that is not harmonic, despite having all algebraic properties of the quantum harmonic oscillator. This raises the question where the usual algebraic argument -- implying integer gaps -- fails. The answer is illuminating and covers a surprisingly rich range of physical phenomena for such a simple model.

Keywords

Cite

@article{arxiv.2603.23774,
  title  = {The quantum harmonic oscillator on a circle -- fragmentation of the algebraic method},
  author = {Daniel Burgarth and Paolo Facchi},
  journal= {arXiv preprint arXiv:2603.23774},
  year   = {2026}
}

Comments

20 pages, 8 figures