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Related papers: Tomography in Loop Quantum Cosmology

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Phase-space representations are a family of methods for dynamics of both bosonic and fermionic systems, that work by mapping the system's density matrix to a quasi-probability density and the Liouville-von Neumann equation of the…

Quantum Gases · Physics 2023-04-24 F. Rousse , O. Eriksson , M. Ogren

The spatially flat Friedman-Robertson-Walker (FRW) cosmological model with a massless scalar field in loop quantum cosmology admits a description in terms of a completely solvable model. This has been used to prove that: i) the quantum…

General Relativity and Quantum Cosmology · Physics 2015-03-19 Alejandro Corichi , Edison Montoya

We develop a semi-classical approximation for the scar function in the Weyl-Wigner representation in the neighborhood of a classically unstable periodic orbit of chaotic two dimensional systems. The prediction of hyperbolic fringes,…

Quantum Physics · Physics 2009-11-13 Alejandro M. F. Rivas

Distances between quantum states are reviewed within the framework of the tomographic-probability representation. Tomographic approach is based on observed probabilities and is straightforward for data processing. Different states are…

Quantum Physics · Physics 2010-10-12 S. N. Filippov , V. I. Man'ko

Emitter ensembles constitute a fundamental component in quantum optical technologies, yet efficient and accurate simulation of large ensembles remains challenging. Here, we formulate a truncated Wigner approximation (TWA) for…

Quantum Physics · Physics 2026-02-27 Lewis Ruks

The $f(R, T)$ theory of gravity extends general relativity (GR) by allowing the gravitational Lagrangian to depend on both the Ricci scalar $R$ and the trace of the energy-momentum tensor $T$. The resulting matter-geometry coupling…

General Relativity and Quantum Cosmology · Physics 2026-02-16 Serkan Doruk Hazinedar , Yaghoub Heydarzade , Shahram Jalalzadeh

We propose a quantum process tomography scheme that utilizes two-mode squeezed vacuum to realize the parameter estimation with Heisenberg scaling. The objective is to estimate a rotating angle of polarization and parity detection is used as…

Quantum Physics · Physics 2018-06-27 Jian-Dong Zhang , Zi-Jing Zhang , Long-Zhu Cen , Yuan Zhao

For the visualization of quantum states, the approach based on Wigner functions can be very effective. Homodyne detection has been extensively used to obtain the density matrix, Wigner functions and tomographic reconstructions of optical…

Quantum Physics · Physics 2019-11-25 Peter Vasil'ev , Richard Penty , Ian White

A spatially flat Friedmann-Robertson-Walker(FRW) cosmological model with generalized Chaplygin gas is studied in the context of scalar-metric formulation of cosmology. Schutz's mechanism for the perfect fluid is applied with generalized…

General Relativity and Quantum Cosmology · Physics 2011-06-24 Barun Majumder

We propose a new method for obtaining an effective Friedmann-Lema\^itre-Robertson-Walker (FLRW) cosmology from the quantum gravity dynamics of group field theory (GFT), based on the idea that an FLRW universe is characterised by a few…

General Relativity and Quantum Cosmology · Physics 2022-03-10 Steffen Gielen , Luca Marchetti , Daniele Oriti , Axel Polaczek

The use of non-regular representations of the Heisenberg-Weyl commutation relations has proved to be useful for studying conceptual and technical issues in quantum gravity. Of particular relevance is the study of Loop Quantum Cosmology…

General Relativity and Quantum Cosmology · Physics 2011-04-11 Alejandro Corichi , Tatjana Vukasinac , Jose A. Zapata

In this paper, we investigate the time evolution of quantum coherence -- the off-diagonal elements of the density matrix of a multistate quantum system -- from the perspective of the Wigner-Moyal formalism. This approach provides an exact…

Quantum Physics · Physics 2023-09-18 Austin T. Green , Craig C. Martens

The adaptation of Wigner's induced representation for a relativistic quantum theory making possible the construction of wavepackets and admitting covariant expectation values for the coordinate operator x^\mu introduces a foliation on the…

Quantum Physics · Physics 2015-06-11 Lawrence Horwitz

Tomograms introduced for the description of quantum states in terms of probability distributions are shown to be related to a standard star-product quantization with appropriate kernels. Examples of symplectic tomograms and spin tomograms…

Quantum Physics · Physics 2017-08-23 Olga V. Man'ko , Vladimir I. Man'ko , Giuseppe Marmo

The probability representation of quantum and classical statistical mechanics is discussed. Symplectic tomography, center-of-mass tomography, and spin tomography are studied. The connection of tomographic probabilities with dynamic…

Quantum Physics · Physics 2015-05-27 Margarita A. Man'ko , Vladimir I. Man'ko

We introduce the parafermionic truncated Wigner approximation ($p$TWA), a semiclassical phase-space framework for simulating the nonequilibrium dynamics of lattice systems with fractional exchange statistics. The method extends truncated…

Strongly Correlated Electrons · Physics 2026-04-01 Javad Vahedi , Martin Garttner

A flat Fiedmann-Robertson-Walker (FRW) multi-scalar field cosmology is studied with a particular potential of the form $ \rm V(\phi,\sigma)=V_0 e^{-\lambda_1 \phi-\lambda_2 \sigma}$, which emerges as a relation between the time derivatives…

General Relativity and Quantum Cosmology · Physics 2019-11-21 J. Socorro , Omar E. Núñez , Rafael Hernández-Jiménez

A model for measurement in collapse-free nonrelativistic fermionic quantum field theory is presented. In addition to local propagation and effectively-local interactions, the model incorporates explicit representations of localized…

Quantum Physics · Physics 2011-06-02 Mark A. Rubin

We have calculated the admittance of a two-dimensional quantum point contact (QPC) using a novel variant of the Wigner distribution function (WDF) formalism. In the semiclassical approximation, a Boltzman-like equation is derived for the…

Condensed Matter · Physics 2016-08-31 Igor E. Aronov , Gennady P. Berman , David K. Campbell , Sergey V. Dudiy

The systems with multimode nonstationary Hamiltonians quadratic in position and momentum operators are reviewed. The tomographic probability distributions (tomograms) for the Fock states and Gaussian states of the quadratic systems are…

Quantum Physics · Physics 2007-05-23 V. I. Man'ko , V. A. Sharapov , E. V. Shchukin
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