Density matrices and entropy operator for non-Hermitian quantum mechanics

Fuente: arXiv
Enregistré dans:
Détails bibliographiques
Auteurs principaux: Bagarello, Fabio, Gargano, Francesco, Saluto, Lidia
Format: Preprint
Publié: 2025
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866909462666674176
author Bagarello, Fabio
Gargano, Francesco
Saluto, Lidia
author_facet Bagarello, Fabio
Gargano, Francesco
Saluto, Lidia
contents In this paper we consider density matrices operator related to non-Hermitian Hamiltonians. In particular, we analyse two natural extensions of what is usually called a density matrix operator (DM), of pure states and of the entropy operator: we first consider those {\em operators} which are simply similar to a standard DM, and then we discuss those which are intertwined with a DM by a third, non invertible, operator, giving rise to waht we call Riesz Density Matrix operator (RDM). After introducing the mathematical framework, we apply the framework to a couple of applications. The first application is related to a non-Hermitian Hamiltonian describing gain and loss phenomena, widely considered in the context of $PT$-quantum mechanics. The second application is related to a finite-dimensional version of the Swanson Hamiltonian, never considered before, and addresses the problem of deriving a milder version of the RDM when exceptional points form in the system.
format Preprint
id arxiv_https___arxiv_org_abs_2501_11537
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Density matrices and entropy operator for non-Hermitian quantum mechanics
Bagarello, Fabio
Gargano, Francesco
Saluto, Lidia
Mathematical Physics
Quantum Physics
In this paper we consider density matrices operator related to non-Hermitian Hamiltonians. In particular, we analyse two natural extensions of what is usually called a density matrix operator (DM), of pure states and of the entropy operator: we first consider those {\em operators} which are simply similar to a standard DM, and then we discuss those which are intertwined with a DM by a third, non invertible, operator, giving rise to waht we call Riesz Density Matrix operator (RDM). After introducing the mathematical framework, we apply the framework to a couple of applications. The first application is related to a non-Hermitian Hamiltonian describing gain and loss phenomena, widely considered in the context of $PT$-quantum mechanics. The second application is related to a finite-dimensional version of the Swanson Hamiltonian, never considered before, and addresses the problem of deriving a milder version of the RDM when exceptional points form in the system.
title Density matrices and entropy operator for non-Hermitian quantum mechanics
topic Mathematical Physics
Quantum Physics
url https://arxiv.org/abs/2501.11537