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Related papers: Semiclassical Statistical Mechanics

200 papers

A formalism for quantum many-body systems is proposed through a semiclassical treatment in phase space, allowing us to establish a stochastic thermodynamics incorporating quantum statistics. Specifically, we utilize a stochastic…

Statistical Mechanics · Physics 2024-12-23 Zhaoyu Fei

We study quantum mechanics in the stochastic formulation, using the functional integral approach. The noise term enters the classical action as a local contribution of anticommuting fields. The partition function is not invariant under…

High Energy Physics - Lattice · Physics 2013-11-15 S. Nicolis

We investigate symmetric oscillators, and in particular their quantization, by employing semiclassical and quantum phase functions introduced in the context of Liouville-Green transformations of the Schr\"{o}dinger equation. For anharmonic…

Quantum Physics · Physics 2011-11-10 A. Matzkin , M. Lombardi

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

We show that the one-loop effective action at finite temperature for a scalar field with quartic interaction has the same renormalized expression as at zero temperature if written in terms of a certain classical field $\phi_c$, and if we…

High Energy Physics - Phenomenology · Physics 2014-11-21 A. Bessa , F. T. Brandt , C. A. A. de Carvalho , E. S. Fraga

We compute thermal and quantum fluctuations in the background of a domain wall in a scalar field theory at finite temperature using the exact scalar propagator in the subspace orthogonal to the wall's translational mode. The propagator…

High Energy Physics - Phenomenology · Physics 2014-11-17 Carlos A. A. de Carvalho

Employing the path integral approach, we calculate the semiclassical equilibrium density matrix of a particle moving in a nonlinear potential field for coordinates near the top of a potential barrier. As the temperature is decreased, near a…

Quantum Physics · Physics 2015-06-26 F. J. Weiper , J. Ankerhold , H. Grabert

Using the new variational approach proposed recently for a systematic improvement of the locally harmonic Feynman-Kleinert approximation to path integrals we calculate the partition function of the anharmonic oscillator for all temperatures…

High Energy Physics - Theory · Physics 2009-10-28 H. Kleinert , H. Meyer

We derive a stochastic path integral representation of counting statistics in semi-classical systems. The formalism is introduced on the simple case of a single chaotic cavity with two quantum point contacts, and then further generalized to…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 S. Pilgram , A. N. Jordan , E. V. Sukhorukov , M. Buttiker

In the thermodynamics of nanoscopic systems the relation between classical and quantum mechanical description is of particular importance. To scrutinize this correspondence we study an anharmonic oscillator driven by a periodic external…

Statistical Mechanics · Physics 2020-08-26 Mattes Heerwagen , Andreas Engel

Semiclassical methods are essential in analyzing quantum mechanical systems. Although they generally produce approximate results, relatively rare potentials exist for which these methods are exact. Such intriguing potentials serve as…

Quantum Physics · Physics 2024-08-30 Asim Gangopadhyaya , Jonathan Bougie , Constantin Rasinariu

We calculate within a semiclassical approximation the autocorrelation function of cross sections. The starting point is the semiclassical expression for the diagonal matrix elements of an operator. For general operators with a smooth…

Chaotic Dynamics · Physics 2007-08-22 Bruno Eckhardt , Shmuel Fishman , Imre Varga

At high temperature the infrared modes of a weakly coupled quantum field theory can be treated nonperturbatively in real time using the classical field approximation. We use this to introduce a nonperturbative approach to the calculation of…

High Energy Physics - Phenomenology · Physics 2009-11-07 Gert Aarts

The semiclassical formula for the coherent-state propagator is written in terms of complex classical trajectories of an equivalent classical system. Depending on the parameters involved, more than one trajectory may contribute to the…

Quantum Physics · Physics 2015-05-19 A. D. Ribeiro

We propose a way to study one-dimensional statistical mechanics models with complex-valued action using transfer operators. The argument consists of two steps. First, the contour of integration is deformed so that the associated transfer…

Mathematical Physics · Physics 2016-11-10 Margherita Disertori , Sasha Sodin

We discuss some aspects of a recently proposed semi-classical transport theory for QCD plasmas based on coloured point particles. This includes the derivation of effective transport equations for mean fields and fluctuations which relies on…

High Energy Physics - Phenomenology · Physics 2017-08-23 Daniel F. Litim

We focus attention upon the thermal statistics of the classical analogs of quasi-probabilities's (QP) in phase space for the important case of quadratic Hamiltonians. We consider the three more important OPs: 1) Wigner's, $P$-, and…

Statistical Mechanics · Physics 2015-11-16 Flavia Pennini , Angel Plastino , Mario C. Rocca

The basic idea of a microscopic understanding of Thermodynamics is to derive its main features from a microscopic probability distribution. In such a vein, we investigate the thermal statistics of quasi-probabilities's semi-classical…

Statistical Mechanics · Physics 2016-09-20 F. Pennini , A. Plastino , M. C. Rocca

We develop a semiclassical density functional theory in the context of quantum dots. Coulomb blockade conductance oscillations have been measured in several experiments using nanostructured quantum dots. The statistical properties of these…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 Denis Ullmo , Tatsuro Nagano , Steven Tomsovic , Harold U. Baranger

We describe a method to compute thermodynamic quantities in the harmonic approximation for identical bosons and fermions in an external confining field. We use the canonical partition function where only energies and their degeneracies…

Quantum Physics · Physics 2012-02-16 J. R. Armstrong , N. T. Zinner , D. V. Fedorov , A. S. Jensen