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Related papers: Multi-time correlations in the positive-P, Q, and …

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We study solutions of the collisionless Boltzmann equation (CBE) in a functional Koopman representation. This facilitates the use of linear spectral techniques characteristic of the analysis of Schrodinger-type equations. For illustrative…

Astrophysics of Galaxies · Physics 2024-06-25 Keir Darling , Lawrence M. Widrow

Covariant phase observables are obtained by defining simple conditions for mappings from the set of phase wave functions (unit vectors of the Hardy space) to the set of phase probability densities. The existence of phase probability density…

Quantum Physics · Physics 2015-06-26 Juha-Pekka Pellonpaa

We investigate bicomplex Hamiltonian systems in the framework of an analogous version of the Schrodinger equation. Since in such a setting three different types of conjugates of bicomplex numbers appear, each is found to define in a natural…

Mathematical Physics · Physics 2015-11-23 Bijan Bagchi , Abhijit Banerjee

By using dynamical invariants theory, Hassoul et al. [1,2] investigate the quantum dynamics of two (2D) and three (3D) dimensional time-dependent coupled oscillators. They claim that, in the 2D case, introducing two pairs of annihilation…

Quantum Physics · Physics 2023-04-19 R. Zerimeche , N. Mana , M. Sekhri , N. Amaouche , M. Maamache

The quantum-mechanical state vector is not directly observable even though it is the fundamental variable that appears in Schrodinger's equation. In conventional time-dependent perturbation theory, the state vector must be calculated before…

Quantum Physics · Physics 2009-11-07 J. D. Franson , Michelle M. Donegan

Applying the time-dependent variational principle of Balian and V\'en\'eroni, we derive variational approximations for multi-time correlation functions in $\Phi^4$ field theory. We assume first that the initial state is given and…

High Energy Physics - Theory · Physics 2009-10-31 Cécile Martin

We study the time evolution of bosonic systems where multiple driven bosonic modes of light interact with multiple mechanical resonators through arbitrary, time-dependent, optomechanical-like interactions. We find the analytical expression…

Quantum Physics · Physics 2019-08-27 David Edward Bruschi

Phase-space representations are of increasing importance as a viable and successful means to study exponentially complex quantum many-body systems from first principles. This review traces the background of these methods, starting from the…

Quantum Physics · Physics 2009-11-13 P. D. Drummond , P. Deuar , J. F. Corney

Complex numbers appear in the Hilbert space formulation of quantum mechanics, but not in the formulation in phase space. Quantum symmetries are described by complex, unitary or antiunitary operators defining ray representations in Hilbert…

Quantum Physics · Physics 2009-11-11 A. J. Bracken

We construct phase space localizing operators in all dimensions. These are frequency localized variants of the conditional expectation operator related to a dyadic stopping time. Our construction is an improvement over the so-called phase…

Classical Analysis and ODEs · Mathematics 2024-02-20 Marco Fraccaroli , Olli Saari , Christoph Thiele

Operators in quantum mechanics - either observables, density or evolution operators, unitary or not - can be represented by c-numbers in operator bases. The position and momentum bases are in one to one correspondence with lagrangian planes…

Quantum Physics · Physics 2018-08-03 Marcos Saraceno , Alfredo M. Ozorio de Almeida

Higher (2nd)-order Wigner distribution function in quantum phase space for entangled bi-modal coherent states, a representative of higher (2nd)-order optical-polarization, is introduced by generalizing kernel (transiting) operator in…

Quantum Physics · Physics 2012-04-04 Ravi S. Singh , Sunil P. Singh , Lallan Yadava , Gyaneshwar K. Gupta

Mutual unbiasedness of the eigenstates of phase-space operators-such as position and momentum, or their standard coarse grained versions-exists only in the limiting case of infinite squeezing. In [Phys. Rev. Lett. 120, 040403 (2018)] it was…

Quantum Physics · Physics 2018-05-09 E. C. Paul , S. P. Walborn , D. S. Tasca , Lukasz Rudnicki

Coherent-state representations are a standard tool to deal with continuous-variable systems, as they allow one to efficiently visualize quantum states in phase space. Here, we work out an alternative basis consisting of monomials on the…

Quantum Physics · Physics 2024-06-05 A. Z. Goldberg , A. B. Klimov , G. Leuchs , L. L. Sanchez-Soto

The quantum dynamics of open many-body systems poses a challenge for computational approaches. Here we develop a stochastic scheme based on the positive P phase-space representation to study the nonequilibrium dynamics of coupled spin-boson…

Quantum Physics · Physics 2015-06-11 Stephan Mandt , Darius Sadri , Andrew A. Houck , Hakan E. Türeci

The dynamical behaviour of many-body systems is often richer than what can be anticipated from their static properties. Here we show that in closed quantum systems this becomes evident by considering time-integrated observables as order…

Statistical Mechanics · Physics 2013-06-14 James M. Hickey , Sam Genway , Igor Lesanovsky , Juan P. Garrahan

A mixed quantal-semiquantal theory is presented in which the semiquantal squeezed-state wave packet describes the heavy degrees of freedom. We first derive mean-field equations of motion from the time-dependent variational principle. Then,…

Chemical Physics · Physics 2016-02-08 Koji Ando

Dynamical systems associated with a q-deformed two dimensional phase space are studied as effective dynamical systems described by ordinary variables. In quantum theory, the momentum operator in such a deformed phase space becomes a…

Mathematical Physics · Physics 2011-03-15 S. Naka , H. Toyoda , T. Takanashi

The ability of matter to be superposed at two different locations while being intrinsically connected by a quantum phase is among the most counterintuitive predictions of quantum physics. While such superpositions have been created for a…

Quantum Physics · Physics 2016-04-13 D. Kienzler , C. Flühmann , V. Negnevitsky , H. -Y. Lo , M. Marinelli , D. Nadlinger , J. P. Home

Formal structure of phase-space path integrals based on different types of operator orderings is analysed.

Statistical Mechanics · Physics 2009-06-16 L. I. Plimak