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Physical systems that dissipate, mix and develop turbulence also irreversibly transport statistical density. In statistical physics, laws for these processes have a mathematical form and tractability that depends on whether the description…

Statistical Mechanics · Physics 2022-11-16 Swetamber Das , Jason R. Green

A non-Hermitean extension of paradigmatic Wishart random matrices is introduced to set up a theoretical framework for statistical analysis of (real, complex and real quaternion) stochastic time series representing two "remote" complex…

Mathematical Physics · Physics 2011-02-07 Eugene Kanzieper , Navinder Singh

We present an algebraic algorithm for quantum state tomography that leverages measurements of certain observables to estimate structured entries of the underlying density matrix. Under low-rank assumptions, the remaining entries can be…

Quantum Physics · Physics 2026-02-18 Shakir Showkat Sofi , Charlotte Vermeylen , Lieven De Lathauwer

We consider an ensemble of large non-Hermitian random matrices of the form $\hat{H}+i\hat{A}_s$, where $\hat{H}$ and $\hat{A}_s$ are Hermitian statistically independent random $N\times N$ matrices. We demonstrate the existence of a new…

Condensed Matter · Physics 2016-08-31 Yan V. Fyodorov , Boris A. Khoruzhenko , Hans-Juergen Sommers

We present two new aspects for the recently proposed algorithms for matrix manipulating based on the special encoding the matrix elements into the superposition state of a quantum system. First aspect is the controlled measurement which…

Quantum Physics · Physics 2025-01-28 Edward B. Fel'dman , Alexander I. Zenchuk , Wentao Qi , Junde Wu

Hybrid machine learning based on Hamiltonian formulations has recently been successfully demonstrated for simple mechanical systems, both energy conserving and not energy conserving. We introduce a pseudo-Hamiltonian formulation that is a…

Machine Learning · Computer Science 2023-02-15 Sølve Eidnes , Alexander J. Stasik , Camilla Sterud , Eivind Bøhn , Signe Riemer-Sørensen

For configurational space of arbitrary dimension a strict form of the uncertainty principle has been obtained, which takes into account the dependence of inequality limit on the effective number of pure states present in given statistical…

Quantum Physics · Physics 2009-11-06 M. U. Karelin , A. M. Lazaruk

New inequalities for tomographic probability distributions and density matrices of qutrit states are obtained by means of generalization of qubit portrait method. The approach based on the qudit portrait method to get new entropic…

Quantum Physics · Physics 2019-02-12 V. N. Chernega , O. V. Man'ko , V. I. Man'ko

We introduce a class of intrinsic symmetry-protected topological mixed-state(mSPT) in open quantum systems that feature modulated symmetries, such as dipole and subsystem symmetries. Intriguingly, these mSPT phases cannot be realized as the…

Quantum Physics · Physics 2024-07-15 Yizhi You , Masaki Oshikawa

It is known that the standard and the inverted harmonic oscillator are different. Replacing thus of {\omega} by i{\omega} in the regular oscillator is necessary going to give the inverted oscillator H^{r}. This replacement would lead to…

Quantum Physics · Physics 2022-04-25 Rahma Zerimeche , Rostom Moufok , Nadjat Amaouche , Mustapha Maamache

Open classical and quantum systems have attracted great interest in the past two decades. These include systems described by non-Hermitian Hamiltonians with parity-time $(\mathcal{PT})$ symmetry that are best understood as systems with…

Quantum Physics · Physics 2022-03-22 Kaustubh S. Agarwal , Jacob Muldoon , Yogesh N. Joglekar

This paper presents new theory and methodology for the Bayesian estimation of overfitted hidden Markov models, with finite state space. The goal is then to achieve posterior emptying of extra states. A prior configuration is constructed…

Methodology · Statistics 2016-02-09 Zoé van Havre , Judith Rousseau , Nicole White , Kerrie Mengersen

In this article we derive a useful expectation identity using the language of quantum statistical mechanics, where density matrices represent the state of knowledge about the system. This identity allows to establish relations between…

Quantum Physics · Physics 2024-10-29 Boris Maulén , Sergio Davis , Daniel Pons

In a differential approach elaborated, we study the evolution of the parameters of Gaussian, mixed, continuous variable density matrices, whose dynamics are given by Hermitian Hamiltonians expressed as quadratic forms of the position and…

Quantum Physics · Physics 2020-05-26 Julio A. López-Saldívar , Margarita A. Man'ko , Vladimir I. Man'ko

The current applications of non-Hermitian but ${\cal PT}-$symmetric Hamiltonians $H$ cover several, mutually not too closely connected subdomains of quantum physics. Mathematically, the split between the open and closed systems can be…

Quantum Physics · Physics 2021-10-29 Miloslav Znojil

The positive and not completely positive maps of density matrices, which are contractive maps, are discussed as elements of a semigroup. A new kind of positive map (the purification map), which is nonlinear map, is introduced. The density…

Quantum Physics · Physics 2007-05-25 V. I. Man'ko , G. Marmo , E. C. G. Sudarshan , F. Zaccaria

Optimized, necessary and sufficient conditions for the identification of the Schmidt number will be derived in terms of general Hermitian operators. These conditions apply to arbitrary mixed quantum states. The optimization procedure…

Quantum Physics · Physics 2011-04-14 J. Sperling , W. Vogel

Higher-fidelity entry simulations can be enabled by integrating finer thermo-chemistry models into compressible flow physics. One such class of models are State-to-State (StS) kinetics, which explicitly track species populations among…

Computational Physics · Physics 2024-03-15 Ayoub Gouasmi , Scott Murman

Two non-Hermitian PT-symmetric Hamiltonian systems are reconsidered by means of the algebraic method which was originally proposed for the pseudo-Hermitian Hamiltonian systems rather than for the PT-symmetric ones. Compared with the way…

Quantum Physics · Physics 2018-01-17 Jun-Qing Li , Qian Li , Yan-Gang Miao

The infinitesimal transition probability operator for a continuous-time discrete-state Markov process, $\mathcal{Q}$, can be decomposed into a symmetric and a skew-symmetric parts. As recently shown for the case of diffusion processes,…

Mathematical Physics · Physics 2013-04-09 Hong Qian