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Related papers: Null bootstrap for non-Hermitian Hamiltonians

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Quantum nonclassicality is the basic building stone for the vast majority of quantum information applications and methods of its generation are at the forefront of research. One of the obstacles any method needs to clear is the looming…

Quantum Physics · Physics 2017-02-28 Petr Marek , Lukas Lachman , Lukas Slodicka , Radim Filip

In recent years, non-Hermitian phases in classical and quantum systems have garnered significant attention. In particular, their intriguing band geometry offers a platform for exploring unique topological states and unconventional quantum…

Mesoscale and Nanoscale Physics · Physics 2023-10-10 Ayan Banerjee , Arka Bandyopadhyay , Ronika Sarkar , Awadhesh Narayan

We show that a polynomial H(N) of degree N of a harmonic oscillator hamiltonian allows us to devise a fully solvable continuous quantum system for which the first N discrete energy eigenvalues can be chosen at will. In general such a choice…

Quantum Physics · Physics 2021-02-02 Ole Steuernagel , Andrei Klimov

A review is given on the foundations and applications of non-Hermitian classical and quantum physics. First, key theorems and central concepts in non-Hermitian linear algebra, including Jordan normal form, biorthogonality, exceptional…

Mesoscale and Nanoscale Physics · Physics 2021-04-28 Yuto Ashida , Zongping Gong , Masahito Ueda

In the global framework of quantum theory the individual quantum systems seem clearly separated into two families with the respective manifestly Hermitian and hiddenly Hermitian operators of their Hamiltonian. In the light of certain…

Quantum Physics · Physics 2018-05-15 Miloslav Znojil

The Hamiltonian H specifies the energy levels and time evolution of a quantum theory. A standard axiom of quantum mechanics requires that H be Hermitian because Hermiticity guarantees that the energy spectrum is real and that time evolution…

High Energy Physics - Theory · Physics 2008-11-26 Carl M. Bender

In this work we report on a new bootstrap method for quantum mechanical problems that closely mirrors the setup from conformal field theory (CFT). We use the equations of motion to develop an analogue of the conformal block expansion for…

High Energy Physics - Theory · Physics 2023-04-26 Colin Oscar Nancarrow , Yuan Xin

We study the scalar modes of linear perturbations in loop quantum cosmology. This is done on a lattice where each cell is taken to be homogeneous and isotropic and can be quantized via standard homogeneous loop quantum cosmology techniques.…

General Relativity and Quantum Cosmology · Physics 2015-06-05 Edward Wilson-Ewing

We find that a broken PT-symmetry operator when interacts with suitable Hermitian operator, new system becomes completely un-broken PT symmetry. Further on varying the contribution of Hermiticity one can delay or control the broken…

Quantum Physics · Physics 2020-04-14 Biswanath Rath

The assumption that quantum systems relax to a stationary state in the long-time limit underpins statistical physics and much of our intuitive understanding of scientific phenomena. For isolated systems this follows from the eigenstate…

Quantum Physics · Physics 2019-04-16 Berislav Buca , Joseph Tindall , Dieter Jaksch

Recently, apparent nonphysical implications of non-Hermitian quantum mechanics (NHQM) have been discussed in the literature. In particular, the apparent violation of the no-signaling theorem, discrimination of nonorthogonal states, and the…

Quantum Physics · Physics 2019-12-25 Chia-Yi Ju , Adam Miranowicz , Guang-Yin Chen , Franco Nori

This paper considers the problem of robust stability for a class of uncertain quantum systems subject to unknown perturbations in the system Hamiltonian. Some general stability results are given for different classes of perturbations to the…

Quantum Physics · Physics 2015-06-04 Ian R. Petersen , Valery Ugrinovskii , Matthew R. James

In contrast to classical systems, actual implementation of non-Hermitian Hamiltonian dynamics for quantum systems is a challenge because the processes of energy gain and dissipation are based on the underlying Hermitian system-environment…

Quantum Physics · Physics 2020-10-23 R. Grimaudo , A. Messina , A. Sergi , N. V. Vitanov , S. N. Filippov

Achieving noise resilience is an outstanding challenge in Hamiltonian-based quantum computation. To this end, energy-gap protection provides a promising approach, where the desired quantum dynamics are encoded into the ground space of a…

Quantum Physics · Physics 2024-12-11 Yingkang Cao , Suying Liu , Haowei Deng , Zihan Xia , Xiaodi Wu , Yu-Xin Wang

We perform an extensive bootstrap study of Hermitian and non-Hermitian theories based on the novel analytic continuation of $\langle\phi^n\rangle$ or $\langle(i\phi)^n\rangle$ in $n$. We first use the quantum harmonic oscillator to…

High Energy Physics - Theory · Physics 2025-02-19 Wenliang Li

Positive definiteness of a Hamiltonian expanded about an equilibrium point provides only a necessary condition for stability, a criterion known as Dirichlet's theorem. The reason that this criterion is not necessary for stability is because…

Plasma Physics · Physics 2016-05-17 Caroline G. L. Martins , P. J. Morison , C. Curry

Over the past decade classical optical systems with gain or loss, modelled by non-Hermitian parity-time symmetric Hamiltonians, have been deeply investigated. Yet, their applicability to the quantum domain with number-resolved photonic…

Quantum Physics · Physics 2024-05-15 Ross Wakefield , Anthony Laing , Yogesh N. Joglekar

We show how generic non-Hermitian tight-binding lattice models can be realized in an unconditional, quantum-mechanically consistent manner by constructing an appropriate open quantum system. We focus on the quantum steady states of such…

Quantum Physics · Physics 2022-02-21 Alexander McDonald , Ryo Hanai , Aashish A. Clerk

The unavoidable interaction of quantum systems with their environment usually results in the loss of desired quantum resources. Suitably chosen system Hamiltonians, however, can, to some extent, counteract such detrimental decay, giving…

Quantum Physics · Physics 2018-10-03 Łukasz Rudnicki , Clemens Gneiting

The coupling of non-Hermitian PT-symmetric Hamiltonians to standard Hermitian Hamiltonians, each of which individually has a real energy spectrum, is explored by means of a number of soluble models. It is found that in all cases the energy…

High Energy Physics - Theory · Physics 2008-11-26 Carl M. Bender , Hugh F. Jones