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The Weyl-Wigner representation of quantum mechanics allows one to map the density operator in a function in phase space - the Wigner function - which acts like a probability distribution. In the context of statistical mechanics, this…

Quantum Physics · Physics 2023-08-31 Marcos Gil de Oliveira , Alfredo Miguel Ozorio de Almeida

The spectral gap occupies a role of central importance in many open problems in physics. We present an approach for evaluating the spectral gap of a Hamiltonian from a simple ratio of two expectation values, both of which are evaluated…

Quantum Physics · Physics 2026-01-26 Jacob M. Leamer , Alicia B. Magann , Gerard McCaul , Denys I. Bondar

Quantum systems with constraints are often considered in modern theoretical physcics. All realistic field models based on the idea of gauge symmetry are of this type. A partial case of constraints being linear in coordinate and momenta…

Mathematical Physics · Physics 2007-05-23 O. Yu. Shvedov

We give a geometric proof of a theorem of Weyl on the continuous part of the spectrum of Sturm-Liouville operators on the half-line with asymptotically constant coefficients. Earlier proofs due to Weyl and Kodaira depend on special features…

Operator Algebras · Mathematics 2019-08-30 Nigel Higson , Qijun Tan

Exact results are derived on the averaged dynamics of a class of random quantum-dynamical systems in continuous space. Each member of the class is characterized by a Hamiltonian which is the sum of two parts. While one part is…

Quantum Physics · Physics 2016-10-26 Werner Fischer , Hajo Leschke , Peter Mueller

Wigner's quasi-probability distribution function in phase-space is a special (Weyl) representation of the density matrix. It has been useful in describing quantum transport in quantum optics; nuclear physics; decoherence (eg, quantum…

High Energy Physics - Theory · Physics 2008-11-26 Cosmas K Zachos

We find Weyl upper bounds for the quantum open baker's map in the semiclassical limit. For the number of eigenvalues in an annulus, we derive the asymptotic upper bound $\mathcal O(N^\delta)$ where $\delta$ is the dimension of the trapped…

Spectral Theory · Mathematics 2022-02-23 Zhenhao Li

We present a list of formulae useful for Weyl-Heisenberg integral quantizations, with arbitrary weight, of functions or distributions on the plane. Most of these formulae are known, others are original. The list encompasses particular cases…

A method is presented to compute approximate solutions for eigenequations in quantum mechanics with an arbitrary kinetic part. In some cases, the approximate eigenvalues can be analytically determined and they can be lower or upper bounds.…

Quantum Physics · Physics 2012-10-01 Claude Semay

We consider quite general differential operators on the circle with a small random lower order perturbation. We embrace two points a view, the semiclassical and the high energy limits. We show (a) in the semiclassical limit, that the…

Spectral Theory · Mathematics 2011-02-15 William Bordeaux Montrieux

We propose a Wigner quasiprobability distribution function for Hamiltonian systems in spaces of constant curvature --in this paper on hyperboloids--, which returns the correct marginals and has the covariance of the Shapiro functions under…

Quantum Physics · Physics 2015-06-26 Miguel Angel Alonso , George S. Pogosyan , Kurt Bernardo Wolf

It was recently noted that the on-shell Einstein-Hilbert action with York-Gibbons-Hawking boundary term has an imaginary part, proportional to the area of the codimension-2 surfaces on which the boundary normal becomes null. We discuss the…

General Relativity and Quantum Cosmology · Physics 2013-09-13 Norbert Bodendorfer , Yasha Neiman

This paper considers open quantum systems whose dynamic variables satisfy canonical commutation relations and are governed by Markovian Hudson-Parthasarathy quantum stochastic differential equations driven by external bosonic fields. The…

Mathematical Physics · Physics 2015-12-31 Igor G. Vladimirov

The recently introduced resource theory of imaginarity facilitates a systematic investigation into the role of complex numbers in quantum mechanics and quantum information theory. In this work, we propose well-defined measures of…

Quantum Physics · Physics 2025-01-15 Meng-Li Guo , Si-Yin Huang , Bo Li , Shao-Ming Fei

Within the framework of weighted integrable Hamiltonian systems, we study the long-time behavior of the associated statistical ensembles. We construct an action-dependent angular conjugacy that rectifies the nonuniform angular flow into a…

Dynamical Systems · Mathematics 2025-09-29 Xinyu Liu , Yong Li

The Weyl-gauge ($A_0^a=0)$ QCD Hamiltonian is unitarily transformed to a representation in which it is expressed entirely in terms of gauge-invariant quark and gluon fields. In a subspace of gauge-invariant states we have constructed that…

High Energy Physics - Theory · Physics 2007-05-23 Kurt Haller

We study a host of spacetimes where the Weyl curvature may be expressed algebraically in terms of an Abelian field strength. These include Type D spacetimes in four and higher dimensions which obey a simple quadratic relation between the…

High Energy Physics - Theory · Physics 2020-10-28 Rashid Alawadhi , David S. Berman , Bill Spence

This article is concerned with estimations from below for the remainder term in Weyl's law for the spectral counting function of certain rational (2l+1)-dimensional Heisenberg manifolds. Concentrating on the case of odd l, it continues the…

Number Theory · Mathematics 2008-10-14 W. G. Nowak

We define a one-parameter family of two-sided coideals in U_q(gl(n)) and study the corresponding algebras of infinitesimally right invariant functions on the quantum unitary group U_q(n). The Plancherel decomposition of these algebras with…

q-alg · Mathematics 2008-02-03 M. S. Dijkhuizen , M. Noumi

For two-dimensional quantum billiards we derive the partial Weyl law, i.e. the average density of states, for a subset of eigenstates concentrating on an invariant region $\Gamma$ of phase space. The leading term is proportional to the area…

Quantum Physics · Physics 2011-05-03 Arnd Bäcker , Roland Ketzmerick , Steffen Löck , Holger Schanz