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Related papers: On "non-Hermitian Quantum Mechanics"

200 papers

Canonical quantum mechanics postulates Hermitian Hamiltonians to ensure real eigenvalues. Counterintuitively, a non-Hermitian Hamiltonian, satisfying combined parity-time (PT) symmetry, could display entirely real spectra above some…

Optics · Physics 2025-01-23 Jianming Wen , Xiaoshun Jiang , Liang Jiang , Min Xiao

In the context of two particularly interesting non-Hermitian models in quantum mechanics we explore the relationship between the original Hamiltonian H and its Hermitian counterpart h, obtained from H by a similarity transformation, as…

Quantum Physics · Physics 2009-11-10 H. F. Jones

In the context of traditional quantum-control considerations it is conjectured that one of the promising new strategies of the constructive model building could be sought in a non-stationary upgrade of the formalism of PT-symmetric quantum…

Quantum Physics · Physics 2015-07-14 Miloslav Znojil

We review the well-known Hellmann Feynman Theorem (HFT), originally developed for Hermitian systems to facilitate the calculation of forces among the molecules. Our work extends this foundational theorem to the domain of non-Hermitian…

Quantum Physics · Physics 2025-04-02 Gaurav Hajong , Bhabani Prasad Mandal

The {\eta} pseudo PT symmetry theory, denoted by the symbol {\eta}, explores the conditions under which non-Hermitian Hamiltonians can possess real spectra despite the violation of PT symmetry, that is the adjoint of H, denoted H^{{\dag}}…

Quantum Physics · Physics 2024-01-09 Mustapha Maamache , Nour El Houda Absi

A physical requirement on the Hamiltonian operator in quantum mechanics is that it must generate real energy spectrum and unitary time evolution. While the Hamiltonians are Dirac Hermitian in conventional quantum mechanics, they observe…

Mathematical Physics · Physics 2018-07-31 Minyi Huang , Asutosh Kumar , Junde Wu

In this work we will advance farther along a line previously developed concerning our proposal of a time interval operator, on finite dimensional spaces. The time interval operator is Hermitian, and its eigenvalues are time values with a…

Quantum Physics · Physics 2007-05-23 M. Ruzzi , D. Galetti

We revisit the celebrated Hellmann-Feynman theorem (HFT) in the PT invariant non-Hermitian quantum physics framework. We derive a modified version of HFT by changing the definition of inner product and explicitly show that it holds good for…

Quantum Physics · Physics 2023-08-29 Gaurav Hajong , Ranjan Modak , Bhabani Prasad Mandal

Starting with the modified Dirac equations for free massive particles with the $\gamma_5$-extension of the physical mass $m\rightarrow m_1 + \gamma_5 m_2$, we consider equations of relativistic quantum mechanics in the presence of an…

High Energy Physics - Theory · Physics 2014-04-03 V. N. Rodionov

Among ${\cal P}$-pseudo-Hermitian Hamiltonians $H ={\cal P}^{-1} H^\dagger \cal P}$ with real spectra, the ''weakly pseudo-Hermitian" ones (i.e., those employing non-self-adjoint ${\cal P} \neq {\cal P}^\dagger$) form a remarkable…

Mathematical Physics · Physics 2008-04-25 Miloslav Znojil

Although the Hamiltonian in quantum physics has to be a linear operator, it is possible to make quantum systems behave as if their Hamiltonians contained antilinear (i.e., semilinear or conjugate-linear) terms. For any given quantum system,…

Mathematical Physics · Physics 2013-01-03 Michael Eisele

The construction of exactly-solvable models has recently been advanced by considering integrable $T\bar{T}$ deformations and related Hamiltonian deformations in quantum mechanics. We introduce a broader class of non-Hermitian Hamiltonian…

High Energy Physics - Theory · Physics 2023-01-18 Apollonas S. Matsoukas-Roubeas , Federico Roccati , Julien Cornelius , Zhenyu Xu , Aurelia Chenu , Adolfo del Campo

In this review we discuss the connection between two seemingly disparate topics, macroscopic gravity on astrophysical scales and Hamiltonians that are not Hermitian but $PT$ symmetric on microscopic ones. In particular we show that the…

High Energy Physics - Theory · Physics 2015-06-05 Philip D. Mannheim

Describing systems with non-Hermitian (NH) operators remains a challenge in quantum theory due to instabilities (e.g., exceptional points and decoherence) arising from interactions with the environment. We propose a framework to express the…

Quantum Physics · Physics 2025-03-31 Priyanshi Bhasin , Tanmoy Das

We describe a method that allows for a practical application of the theory of pseudo-Hermitian operators to PT-symmetric systems defined on a complex contour. We apply this method to study the Hamiltonians $H=p^2+x^2(ix)^\nu$ with…

Quantum Physics · Physics 2007-05-23 Ali Mostafazadeh

In the complex action theory whose path runs over not only past but also future we study a normalized matrix element of an operator $\hat{\cal O}$ defined in terms of the future state at the latest time $T_B$ and the past state at the…

Quantum Physics · Physics 2016-06-21 Keiichi Nagao , Holger Bech Nielsen

We provide a careful analysis of the generating functional in the path integral formulation of pseudo-Hermitian and in particular PT-symmetric quantum mechanics and show how the metric operator enters the expression for the generating…

Quantum Physics · Physics 2009-11-13 Ali Mostafazadeh

The recently introduced by us two- and three-parameter ($p,q$)- and ($p,q,\mu$)-deformed extensions of the Heisenberg algebra were explored under the condition of their direct link with the respective (nonstandard) deformed quantum…

Quantum Physics · Physics 2019-03-05 A. M. Gavrilik , I. I. Kachurik

This paper provides a connection to the non-Hermitian operators associated with the geometric potential function $s$ and Baker-Hausdorff formula. The geometric quantum potential is considered in a precise condition. The Ri-operator as a…

General Physics · Physics 2023-02-21 Jack Whongius

In principle, non-Hermitian quantum equations of motion can be formulated using as a starting point either the Heisenberg's or the Schr\"odinger's picture of quantum dynamics. Here it is shown in both cases how to map the algebra of…

Quantum Physics · Physics 2011-02-07 Alessandro Sergi