English

Beyond Density Matrices: Geometric Quantum States

Quantum Physics 2021-06-30 v1 Statistical Mechanics Dynamical Systems

Abstract

A quantum system's state is identified with a density matrix. Though their probabilistic interpretation is rooted in ensemble theory, density matrices embody a known shortcoming. They do not completely express an ensemble's physical realization. Conveniently, when working only with the statistical outcomes of projective and positive operator-valued measurements this is not a hindrance. To track ensemble realizations and so remove the shortcoming, we explore geometric quantum states and explain their physical significance. We emphasize two main consequences: one in quantum state manipulation and one in quantum thermodynamics.

Keywords

Cite

@article{arxiv.2008.08682,
  title  = {Beyond Density Matrices: Geometric Quantum States},
  author = {Fabio Anza and James P. Crutchfield},
  journal= {arXiv preprint arXiv:2008.08682},
  year   = {2021}
}

Comments

7 pages, 1 figure; Supplementary Material: 2 pages; http://csc.ucdavis.edu/~cmg/compmech/pubs/rgqs.htm

R2 v1 2026-06-23T17:58:31.695Z