English
Related papers

Related papers: Hermitian versus non-Hermitian representations for…

200 papers

We show that similarity (or equivalent) transformations enable one to construct non-Hermitian operators with real spectrum. In this way we can also prove and generalize the results obtained by other authors by means of a gauge-like…

Quantum Physics · Physics 2016-08-08 Francisco M. Fernández

The Heisenberg picture for non-Hermitian but $\eta$-pseudo-Hermitian Hamiltonian systems is suggested. If a non-Hermitian but $\eta$-pseudo-Hermitian Hamiltonian leads to real second order equations of motion, though their first order…

Quantum Physics · Physics 2016-04-14 Yan-Gang Miao , Zhen-Ming Xu

We provide time-evolution operators, gauge transformations and a perturbative treatment for non-Hermitian Hamiltonian systems, which are explicitly time-dependent. We determine various new equivalence pairs for Hermitian and non-Hermitian…

Quantum Physics · Physics 2009-11-13 Carla Figueira de Morisson Faria , Andreas Fring

In this work we present a general formalism to treat non-Hermitian and noncommutative Hamiltonians. This is done employing the phase-space formalism of quantum mechanics, which allows to write a set of robust maps connecting the Hamitonians…

Quantum Physics · Physics 2019-08-15 Jonas F. G. Santos , Fabricio. S. Luiz , Oscar. S. Duarte , Miled. H. Y. Moussa

In the recently quickly developing context of quantum mechanics of unitary systems using a time-independent non-Hermitian Hamiltonian $H$ (having real spectrum and defined as acting in an unphysical but user-friendly Hilbert space ${\cal…

Quantum Physics · Physics 2022-12-21 Miloslav Znojil

We formulate a systematic algorithm for constructing a whole class of Hermitian position-dependent-mass Hamiltonians which, to lowest order of perturbation theory, allow a description in terms of PT-symmetric Hamiltonians. The method is…

Quantum Physics · Physics 2009-11-11 B. Bagchi , C. Quesne , R. Roychoudhury

Excited bound states are often understood within scattering based theories as resulting from the collision of a particle on a target via a short-range potential. We show that the resulting formalism is non-Hermitian and describe the Hilbert…

Quantum Physics · Physics 2011-11-09 A. Matzkin

In quantum mechanics with minimal length uncertainty relations the Heisenberg-Weyl algebra of the one-dimensional harmonic oscillator is a deformed SU(1,1) algebra. The eigenvalues and eigenstates are constructed algebraically and they form…

Quantum Physics · Physics 2007-12-14 K. Gemba , Z. T. Hlousek , Z. Papp

We study a general class of PT-symmetric tridiagonal Hamiltonians with purely imaginary interaction terms in the quasi-hermitian representation of quantum mechanics. Our general Hamiltonian encompasses many previously studied lattice models…

Quantum Physics · Physics 2016-04-05 Frantisek Ruzicka

In the context of the recent interest in solvable models of scattering mediated by non-Hermitian Hamiltonians (cf. H. F. Jones, Phys. Rev. D 76, 125003 (2007)) we show that and how the well known variability of our ad hoc choice of the…

High Energy Physics - Theory · Physics 2008-11-26 Miloslav Znojil

A complexified von Roos Hamiltonian is considered and a Hermitian first-order intertwining differential operator is used to obtain the related position dependent mass $\eta$-weak-pseudo-Hermitian Hamiltonians. Using a Liouvillean-type…

Quantum Physics · Physics 2009-11-13 Omar Mustafa , S. Habib Mazharimousavi

Non-hermitian systems have gained a lot of interest in recent years. However, notions of chaos and localization in such systems have not reached the same level of maturity as in the Hermitian systems. Here, we consider non-hermitian…

Disordered Systems and Neural Networks · Physics 2022-10-19 Soumi Ghosh , Sparsh Gupta , Manas Kulkarni

In this work, we study the non-hermitian Swanson hamiltonian, particularly the non-PT symmetry phase. We use the formalism of Gel'fand triplet to construct the generalized eigenfunctions and the corresponding spectrum. Depending on the…

Quantum Physics · Physics 2021-12-22 V. Fernández , R. Ramírez , M. Reboiro

We address the problem of coupling non-Hermitian systems, treated as fundamental rather than effective theories, to the electromagnetic field. In such theories the observables are not the $\bs{x}$ and $\bs{p}$ appearing in the Hamiltonian,…

Quantum Physics · Physics 2009-11-13 H. F. Jones

A class of pseudo-hermitian quantum system with an explicit form of the positive-definite metric in the Hilbert space is presented. The general method involves a realization of the basic canonical commutation relations defining the quantum…

Quantum Physics · Physics 2010-03-15 Pijush K. Ghosh

For some time the York time parameter has been identified as a candidate for a physically meaningful time in cosmology. An associated Hamiltonian may be found by solving the Hamiltonian constraint for the momentum conjugate to the York time…

General Relativity and Quantum Cosmology · Physics 2016-03-23 Philipp Roser

The quantum mechanical version of the four kinds of classical canonical transformations is investigated by using non-hermitian operator techniques. To help understand the usefulness of this appoach the eigenvalue problem of a harmonic…

High Energy Physics - Theory · Physics 2009-10-28 Haewon Lee , W. S. l'Yi

We investigate properties of generalized time-dependent q-deformed coherent states for a noncommutative harmonic oscillator. The states are shown to satisfy a generalized version of Heisenberg's uncertainty relations. For the initial value…

Mathematical Physics · Physics 2013-04-19 Sanjib Dey , Andreas Fring , Laure Gouba , Paulo G. Castro

Despite acute interest in the dynamics of non-Hermitian systems, there is a lack of consensus in the mathematical formulation of non-Hermitian quantum mechanics in the community. Different methodologies are used in the literature to study…

Quantum Physics · Physics 2025-03-31 Karin Sim , Nicolò Defenu , Paolo Molignini , R. Chitra

Representation theory is shown to be incomplete in terms of enumerating all integrable limits of quantum systems. As a consequence, one can find exactly solvable Hamiltonians which have apparently strongly broken symmetry. The number of…

Nuclear Theory · Physics 2009-10-30 Dimitri Kusnezov