English
Related papers

Related papers: Approximately Macroscopically Unique States and Qu…

200 papers

Although one can show formally that a time-of-arrival operator cannot exist, one can modify the low momentum behaviour of the operator slightly so that it is self-adjoint. We show that such a modification results in the difficulty that the…

Quantum Physics · Physics 2009-10-31 J. Oppenheim , B. Reznik , W. G. Unruh

We present examples of many-body Wigner quantum systems. The position and the momentum operators ${\bf R}_A$ and ${\bf P}_A,\; A=1,\ldots,n+1$, of the particles are noncanonical and are chosen so that the Heisenberg and the Hamiltonian…

High Energy Physics - Theory · Physics 2009-10-30 T. D. Palev , N. I. Stoilova

Semiclassical mechanics of systems with first-class constraints is developed. Starting from the quantum theory, one investigates such objects as semiclassical states and observables, semiclassical inner product, semiclassical gauge…

High Energy Physics - Theory · Physics 2007-05-23 Oleg Shvedov

This paper is devoted to the construction of what we will call {\em exactly solvable models}, i.e. of quantum mechanical systems described by an Hamiltonian $H$ whose eigenvalues and eigenvectors can be explicitly constructed out of some…

Mathematical Physics · Physics 2016-11-03 Fabio Bagarello

Any account of the emergence of classicality from quantum theory must address the fact that the quantum operators representing positions and momenta do not commute, whereas their classical counterparts suffer no such restrictions. To…

Quantum Physics · Physics 2015-05-13 J. J. Halliwell

In this work, a novel method for using a set of electromagnetic quadrupole fields is presented to implement arbitrary unitary operators on a two-state quantum system of electrons. In addition to analytical derivations of the required…

Quantum Physics · Physics 2022-02-28 Stefan Löffler

We consider the problem of characterizing states of a multipartite quantum system from restricted, quasi-local information, with emphasis on uniquely determined pure states. By leveraging tools from dissipative quantum control theory, we…

Quantum Physics · Physics 2019-06-19 Salini Karuvade , Peter D. Johnson , Francesco Ticozzi , Lorenza Viola

The purpose of the paper is to study the foundations of the main axioms of Quantum Mechanics. From a general study of the mathematical properties of the models used in Physics to represent systems, we prove that the states of a system can…

Mathematical Physics · Physics 2015-07-02 Jean Claude Dutailly

Absolutely maximally entangled (AME) states are typically defined in homogeneous systems. However, the quantum system is more likely to be heterogeneous in a practical setup. In this work we pay attention to the construction of AME states…

Quantum Physics · Physics 2020-02-06 Yi Shen , Lin Chen

Analytical complexity of quantum wavefunction whose argument is extended into the complex plane provides an important information about the potentiality of manifesting complex quantum dynamics such as time-irreversibility, dissipation and…

Statistical Mechanics · Physics 2015-06-17 Hiroaki S. Yamada , Kensuke S. Ikeda

Relations between Hamiltonian mechanics and quantum mechanics are studied. It is stressed that classical mechanics possesses all the specific features of quantum theory: operators, complex variables, probabilities (in case of ergodic…

Quantum Physics · Physics 2007-05-23 L. V. Prokhorov

Inspired by an old idea of von Neumann, we seek a pair of commuting operators X,P which are, in a specific sense, "close" to the canonical non-commuting position and momentum operators, x,p. The construction of such operators is related to…

Quantum Physics · Physics 2009-11-11 J. J. Halliwell

Supmech, which is noncommutative Hamiltonian mechanics \linebreak (NHM) (developed in paper I) with two extra ingredients : positive observable valued measures (PObVMs) [which serve to connect state-induced expectation values and classical…

Mathematical Physics · Physics 2016-02-16 Tulsi Dass

Harper's equation (aka the "almost Mathieu" equation) famously describes the quantum dynamics of an electron on a one dimensional lattice in the presence of an incommensurate potential with magnitude $V$ and wave number $Q$. It has been…

Mesoscale and Nanoscale Physics · Physics 2015-06-29 Yi Zhang , Daniel Bulmash , Akash V. Maharaj , Chao-Ming Jian , Steven A. Kivelson

We show how random unitary dynamics arise from the coupling of an open quantum system to a static environment. Subsequently, we derive a master equation for the reduced system random unitary dynamics and study three specific cases:…

Quantum Physics · Physics 2018-01-17 Chahan M. Kropf , Vyacheslav N. Shatokhin , Andreas Buchleitner

Let M_n be the collection of n x n complex matrices equipped with operator norm. Suppose U, V \in M_n are two unitary matrices, each possessing a gap larger than \Delta in their spectrum, which satisfy ||UV-VU|| \le \epsilon. Then it is…

Operator Algebras · Mathematics 2008-09-04 Tobias J. Osborne

Notions of nonstabilizerness, or "magic", quantify how non-classical quantum states are in a precise sense: states exhibiting low nonstabilizerness preclude quantum advantage. We introduce 'pseudomagic' ensembles of quantum states that,…

Quantum Physics · Physics 2024-05-31 Andi Gu , Lorenzo Leone , Soumik Ghosh , Jens Eisert , Susanne Yelin , Yihui Quek

We have studied the emergence of classical states in the perturbative interaction model. The states which interact with many other degrees of freedom, such as the center of mass of a macro-object, play important role. Although the random…

Quantum Physics · Physics 2016-04-01 Kentaro Urasaki

The work is intended to represent some interesting and apparently peculiar features of entangled system in both pure as well as mixed states level. In the pure state level, we are largely concerned about the existence and characteristics of…

Quantum Physics · Physics 2008-05-15 Indrani Chattopadhyay

The classification of multipartite entanglement is essential as it serves as a resource for various quantum information processing tasks. This study concerns a particular class of highly entangled multipartite states, the so-called…

Quantum Physics · Physics 2024-11-07 N Ramadas , Arul Lakshminarayan