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Related papers: PT Symmetry and the Sign Problem

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The physical condition that the expectation values of physical observables are real quantities is used to give a precise formulation of PT-symmetric quantum mechanics. A mathematically rigorous proof is given to establish the physical…

Quantum Physics · Physics 2009-11-10 Ali Mostafazadeh

We study certain linear and antilinear symmetry generators and involution operators associated with pseudo-Hermitian Hamiltonians and show that the theory of pseudo-Hermitian operators provides a simple explanation for the recent results of…

Mathematical Physics · Physics 2009-11-07 Ali Mostafazadeh

Motivated by the generalization of quantum theory for the case of non-Hermitian Hamiltonians with PT symmetry, we show how a classical cosmological model describes a smooth transition from ordinary dark energy to the phantom one. The model…

General Relativity and Quantum Cosmology · Physics 2009-11-11 A. A. Andrianov , F. Cannata , A. Y. Kamenshchik

Large families of Hamiltonians that are non-Hermitian in the conventional sense have been found to have all eigenvalues real, a fact attributed to an unbroken PT symmetry. The corresponding quantum theories possess an unconventional scalar…

Quantum Physics · Physics 2009-11-11 Zafar Ahmed , Carl M. Bender , M. V. Berry

By adding an imaginary interacting term proportional to ip_1p_2 to the Hamiltonian of a free anisotropic planar oscillator, we construct a new model which is described by the PT-pseudo-Hermitian Hamiltonian with the permutation symmetry of…

Quantum Physics · Physics 2012-04-16 Jun-Qing Li , Yan-Gang Miao

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

This paper investigates finite-dimensional representations of PT-symmetric Hamiltonians. In doing so, it clarifies some of the claims made in earlier papers on PT-symmetric quantum mechanics. In particular, it is shown here that there are…

Quantum Physics · Physics 2015-06-26 Carl M. Bender , Peter N. Meisinger , Qinghai Wang

A transformation of the form x to iy; x,y in R, or an equivalent similarity transformation with a metric operator $\eta$ are shown to transform non-Hermitian PT-symmetric Hamiltonians into Hermitian partner Hamiltonians in Hilbert space.…

Quantum Physics · Physics 2008-10-08 Omar Mustafa , S. Habib Mazharimousavi

We study symmetries of open bosonic systems in the presence of laser pumping. Non-Hermitian Hamiltonians describing these systems can be parity-time (${\cal{PT}}$) symmetric in special cases only. Systems exhibiting this symmetry are…

Quantum Physics · Physics 2020-11-23 Ewelina Lange , Grzegorz Chimczak , Anna Kowalewska-Kudłaszyk , Karol Bartkiewicz

We study the dissipative dynamics of a one-dimensional bosonic system described in terms of the bipartite Bose-Hubbard model with alternating gain and loss. This model exhibits the $\mathcal{PT}$ symmetry under some specific conditions and…

Quantum Gases · Physics 2023-03-07 Cătălin Paşcu Moca , Doru Sticlet , Balázs Dóra , Gergely Zaránd

The action for gravity and the standard model includes, as well as the positive energy fermion and boson fields, negative energy fields. The Hamiltonian for the action leads through a positive and negative energy symmetry of the vacuum to a…

High Energy Physics - Theory · Physics 2007-05-23 J. W. Moffat

The broken and unbroken phases of PT and supersymmetry in optical systems are explored for a complex refractive index profile in the form of a Scarf potential, under the framework of supersymmetric quantum mechanics. The transition from…

Quantum Physics · Physics 2021-07-05 Adipta Pal , Subhrajit Modak , Aradhya Shukla , Prasanta K. Panigrahi

A parity-time (PT) transition is a spectral transition characteristic of non-Hermitian generators; it typically occurs at an exceptional point, where multiple eigenvectors coalesce. The concept of a PT transition has been extended to…

Quantum Physics · Physics 2026-01-01 Yuma Nakanishi , Tomohiro Sasamoto

We propose a non-Hermitian deformation of the Mathieu equation that preserves $\mathcal{PT}$ symmetry and study its spectrum and the transition from $\mathcal{PT}$-unbroken to $\mathcal{PT}$-broken phases. We show that our model not only…

Quantum Physics · Physics 2022-04-29 E. Cavalcanti , N. M. Alvarenga , F. Reis , J. R. Mahon , C. A. Linhares , J. A. Lourenço

$\mathcal{PT}$-symmetric quantum mechanics has been considered an important theoretical framework for understanding physical phenomena in $\mathcal{PT}$-symmetric systems, with a number of $\mathcal{PT}$-symmetry related applications. This…

Quantum Physics · Physics 2019-12-25 Da-Jian Zhang , Qing-hai Wang , Jiangbin Gong

The $\mathcal{PT}$-symmetric non-Hermitian systems have been widely studied and explored both in theory and in experiment these years due to various interesting features. In this work, we focus on the dynamical features of a triple-qubit…

Quantum Physics · Physics 2021-03-24 Jingwei Wen , Chao Zheng , Zhangdong Ye , Tao Xin , Guilu Long

We consider a two-level system such as a two-level atom, interacting with a cavity field mode in the rotating wave approximation, when the atomic transition frequency or the field mode frequency is periodically driven in time. We show that…

We study the $\mathcal{PT} $-symmetry breaking for the scattering problem in a one-dimensional (1D) non-Hermitian tight-binding lattice model with balanced gain and loss distributed on two adjacent sites. In the scattering process the…

Quantum Physics · Physics 2016-03-30 Baogang Zhu , Rong Lü , Shu Chen

The continuity equation relating the change in time of the position probability density to the gradient of the probability current density is generalized to PT-symmetric quantum mechanics. The normalization condition of eigenfunctions is…

Quantum Physics · Physics 2011-07-28 B. Bagchi , C. Quesne , M. Znojil

The Hamiltonian for a PT-symmetric chain of coupled oscillators is constructed. It is shown that if the loss-gain parameter $\gamma$ is uniform for all oscillators, then as the number of oscillators increases, the region of unbroken…

Mathematical Physics · Physics 2014-08-27 Carl M. Bender , Mariagiovanna Gianfreda , S. P. Klevansky