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We analyse the dynamics of expectation values of quantum observables for the time-dependent semiclassical Schr\"odinger equation. To benefit from the positivity of Husimi functions, we switch between observables obtained from Weyl and…

Numerical Analysis · Mathematics 2013-03-19 Johannes Keller , Caroline Lasser

The formalism of classical and quantum mechanics on phase space leads to symplectic and Heisenberg group representations, respectively. The Wigner functions give a representation of the quantum system using classical variables. The…

Quantum Physics · Physics 2007-05-23 Ajay Patwardhan

The Herman--Kluk propagator is a popular semi-classical approximation of the unitary evolution operator in quantum molecular dynamics. In this paper we formulate the Herman--Kluk propagator as a phase space integral and discretise it by…

Numerical Analysis · Mathematics 2016-05-03 Caroline Lasser , David Sattlegger

We systematically derive a linear quantum collision operator for the spinorial Wigner transport equation from the dynamics of a composite quantum system. For suitable two particle interaction potentials, the particular matrix form of the…

Quantum Physics · Physics 2013-07-29 Benjamin A. Stickler , Stefan Possanner

The algebra of polynomials in operators that represent generalized coordinate and momentum and depend on the Planck constant is defined. The Planck constant is treated as the parameter taking values between zero and some nonvanishing $h_0$.…

Quantum Physics · Physics 2007-05-23 S. Prvanovic , Z. Maric

We construct the quantum mechanical evolution operator in the Functional Schrodinger picture - the kernel - for a scalar field in spatially homogeneous FLRW spacetimes when the field is a) free and b) coupled to a spacetime dependent source…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Jurjen F. Koksma , Tomislav Prokopec , Gerasimos I. Rigopoulos

By a quantum version of the Arnold transformation of classical mechanics, all quantum dynamical systems whose classical equations of motion are non-homogeneous linear second-order ordinary differential equations, including systems with…

Quantum Physics · Physics 2011-02-07 Victor Aldaya , Francisco Cossio , Julio Guerrero , Francisco F. Lopez-Ruiz

We study the trajectories of a semiclassical quantum particle under repeated indirect measurement by Kraus operators, in the setting of the quantized torus. In between measurements, the system evolves via either Hamiltonian propagators or…

Mathematical Physics · Physics 2024-03-18 Yonah Borns-Weil , Izak Oltman

We introduce Quantum Time-Frequency Analysis, which expands the approach of Quantum Harmonic Analysis to include modulations of operators in addition to translations. This is done by a projective representation of double-phase space, and we…

Functional Analysis · Mathematics 2024-03-04 Franz Luef , Henry McNulty

Classical mechanics is formulated in complex Hilbert space with the introduction of a commutative product of operators, an antisymmetric bracket, and a quasidensity operator. These are analogues of the star product, the Moyal bracket, and…

Quantum Physics · Physics 2017-02-23 A. J. Bracken

A uniform semiclassical propagator is used to time evolve a wavepacket in a smooth Hamiltonian system at energies for which the underlying classical motion is chaotic. The propagated wavepacket is Fourier transformed to yield a scarred…

chao-dyn · Physics 2009-10-22 Daniel Provost , Paul Brumer

In this article, we study two different types of operators, the localization operator and Weyl transform, on the reduced Heisenberg group with multidimensional center $\mathcal{G}$. The group $\mathcal{G}$ is a quotient group of…

Functional Analysis · Mathematics 2022-11-15 Aparajita Dasgupta , Santosh Kumar Nayak

We consider diffusive systems, regarded as input/output systems with a kernel given as the Fourier--Borel transform of a measure in the left half-plane. Associated with these are a family of weighted Hankel integral operators, and we…

Functional Analysis · Mathematics 2017-04-04 Aolo Bashar Abusaksaka , Jonathan R. Partington

Wigner phase space quasi-probability distribution function is a Fourier transform related to a given quantum mechanical wave function. It is shown that for the wave functions of type $\psi (q)=e^{-aq^2}\phi (q)$, the Wigner function can be…

Mathematical Physics · Physics 2008-01-02 A. Tegmen

We derive a semi-classical nonequilibrium work identity by applying the Wigner-Weyl quantization scheme to the Jarzynski identity for a classical Hamiltonian. This allows us, to the leading order in $\hbar$, to overcome the problem of…

Quantum Physics · Physics 2020-09-25 O. Brodier , K. Mallick , A. M. Ozorio de Almeida

We study the representation and visualization of finite-dimensional quantum systems. In a generalized Wigner representation, multi-spin operators can be decomposed into a symmetry-adapted tensor basis and they are mapped to multiple…

Quantum Physics · Physics 2020-11-30 David Leiner , Robert Zeier , Steffen J. Glaser

The new numerical approach for consideration of quantum dynamics and calculations of the average values of quantum operators and time correlation functions in the Wigner representation of quantum statistical mechanics has been developed.…

Disordered Systems and Neural Networks · Physics 2009-10-31 V. Filinov , Yu. Lozovik , A. Filinov , I. Zacharov , A. Oparin

Transition from quantum to semiclassical behaviour and loss of quantum coherence for inhomogeneous perturbations generated from a non-vacuum initial state in the early Universe is considered in the Heisenberg and the Schr\"odinger…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Julien Lesgourgues , David Polarski , Alexei A. Starobinsky

A system of $N$ non-canonical dynamically free 3D harmonic oscillators is studied. The position and the momentum operators (PM-operators) of the system do not satisfy the canonical commutation relations (CCRs). Instead they obey the weaker…

High Energy Physics - Theory · Physics 2007-05-23 T. D. Palev

We introduce a hybrid quantum-classical framework for efficiently implementing approximate unitary dilations of non-unitary operators with enhanced noise resilience. The method embeds a target non-unitary operator into a subblock of a…

Quantum Physics · Physics 2025-10-23 S. X. Li , Keren Li , J. B. You , Y. -H. Chen , Clemens Gneiting , Franco Nori , X. Q. Shao
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