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Related papers: Pseudospectra in non-Hermitian quantum mechanics

200 papers

We show that a quantum system possessing an exact antilinear symmetry, in particular PT-symmetry, is equivalent to a quantum system having a Hermitian Hamiltonian. We construct the unitary operator relating an arbitrary non-Hermitian…

Quantum Physics · Physics 2008-11-26 Ali Mostafazadeh

A Su-Schrieffer-Heeger model with added PT-symmetric boundary term is studied in the framework of pseudo-hermitian quantum mechanics. For two special cases, a complete set of pseudometrics is constructed in closed form. When complemented…

Mathematical Physics · Physics 2016-04-05 Frantisek Ruzicka

We explain why the main conclusion of Bender et al, hep-th/0511229 [J. Phys. A 39 (2006) 1657] regarding the practical superiority of the non-Hermitian description of PT-symmetric quantum systems over their Hermitian description is not…

High Energy Physics - Theory · Physics 2007-05-23 Ali Mostafazadeh

We investigate complex PT-symmetric potentials, associated with quasi-exactly solvable non-hermitian models involving polynomials and a class of rational functions. We also look for special solutions of intertwining relations of SUSY…

Quantum Physics · Physics 2009-11-06 F. Cannata , M. Ioffe , R. Roychoudhury , P. Roy

In the recent years a generalization of Hermiticity was investigated using a complex deformation H=p^2 +x^2(ix)^\epsilon of the harmonic oscillator Hamiltonian, where \epsilon is a real parameter. These complex Hamiltonians, possessing PT…

Quantum Physics · Physics 2015-05-14 Tomas Ya. Azizov , Carsten Trunk

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

To develop a unitary quantum theory with probabilistic description for pseudo- Hermitian systems one needs to consider the theories in a different Hilbert space endowed with a positive definite metric operator. There are different…

Quantum Physics · Physics 2013-05-10 Ananya Ghatak , Bhabani Prasad Mandal

Many indefinite-metric (often called pseudo-Hermitian or PT-symmetric) quantum models H prove "physical" (i.e., Hermitian with respect to an innovated, ad hoc scalar product) inside a characteristic domain of parameters D. This means that…

Quantum Physics · Physics 2007-05-23 Miloslav Znojil

In quantum theory, a physical observable is represented by a Hermitian operator as it admits real eigenvalues. This stems from the fact that any measuring apparatus that is supposed to measure a physical observable will always yield a real…

Quantum Physics · Physics 2015-12-09 Arun Kumar Pati , Uttam Singh , Urbasi Sinha

We consider a two-parameter non hermitean quantum-mechanical hamiltonian that is invariant under the combined effects of parity and time reversal transformation. Numerical investigation shows that for some values of the potential parameters…

Quantum Physics · Physics 2009-10-31 F. M. Fernandez , R. Guardiola , J. Ros , M. Znojil

Two alternative scenarios are shown possible in Quantum Mechanics working with non-Hermitian $PT-$symmetric form of observables. While, usually, people assume that $P$ is a self-adjoint indefinite metric in Hilbert space (and that their…

Quantum Physics · Physics 2007-05-23 Miloslav Znojil

This study investigates pseudo-Hermitian quantum mechanics, where the Hamiltonian satisfies a modified Hermiticity condition. We extend the uncertainty relation for such systems, demonstrating its equivalence to the standard Hermitian case…

Quantum Physics · Physics 2025-08-11 Boubakeur Khantoul , Bilel Hamil , Amar Benchikha

In the recent years a generalization $H=p^2 +x^2(ix)^\epsilon$ of the harmonic oscillator using a complex deformation was investigated, where \epsilon\ is a real parameter. Here, we will consider the most simple case: \epsilon even and x…

Quantum Physics · Physics 2015-05-30 Tomas Azizov , Carsten Trunk

A quasi-product on the normed space is defined. In addition, the notions of the eigenvectors of a linear operator can be extended for the nonlinear operator. Based on the quasi-product and the generalized eigenvectors, the spectral theorems…

Functional Analysis · Mathematics 2020-02-18 Wen Hsiang Wei

It is well known that an (in general, non-commutative) set of non-Hermitian operators $\Lambda_j$ with real eigenvalues need not necessarily represent observables. We describe a specific class of quantum models in which these operators plus…

Quantum Physics · Physics 2022-08-02 Miloslav Znojil

It is an interesting and open problem to trace the origin of the pseudospin symmetry in nuclear single-particle spectra and its symmetry breaking mechanism in actual nuclei. In this report, we mainly focus on our recent progress on this…

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

We consider the $\mathcal{PT}$-symmetric quantum field theory on the noncommutative spacetime with angular twist and construct its pseudo-Hermitian interpretation. We explore the differences between internal and spatial parities in the…

High Energy Physics - Theory · Physics 2019-10-25 Oleg O. Novikov

When a non-hermitian hamiltonian has a certain symmetry, such as the PT pseudo-hermiticity, it is still possible that the hamiltonian has a real spectrum. In this note, by adding an imaginary potential proportional to ip_1p_2 to the…

Quantum Physics · Physics 2011-10-12 Jun-Qing Li , Yan-Gang Miao

Quantum physics is generally concerned with real eigenvalues due to the unitarity of time evolution. With the introduction of $\mathcal{PT}$ symmetry, a widely accepted consensus is that, even if the Hamiltonian of the system is not…

Quantum Physics · Physics 2023-09-19 Tong Liu , Youguo Wang