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We make a simple observation about two models used to treat the region near the critical temperature of QCD, quasiparticle and matrix models. While they appear very different, we show how these two models might be related. We also present…

High Energy Physics - Phenomenology · Physics 2013-05-06 Kouji Kashiwa , Robert D. Pisarski , Vladimir V. Skokov

The aim of this work is to investigate the application of partial moment approximations to kinetic chemotaxis equations in one and two spatial dimensions. Starting with a kinetic equation for the cell densities we apply a…

Numerical Analysis · Mathematics 2016-08-03 Juliane Ritter , Axel Klar , Florian Schneider

Two-body matrix elements of arbitrary local interactions are written as the sum of separable terms in a way that is well suited for the exchange and pairing channels present in mean-field calculations. The expansion relies on the…

Nuclear Theory · Physics 2010-04-29 L. M. Robledo

For homogeneous initial conditions, Hartree (gaussian) dynamical approximations are known to have problems with thermalization, because of insufficient scattering. We attempt to improve on this by writing an arbitrary density matrix as a…

High Energy Physics - Phenomenology · Physics 2009-10-31 M. Salle , J. Smit , J. C. Vink

The exact semiclassical quantization condition represents a cumbersome series expansion, so that only the main term of it is usually taken into account. We propose a way to find next terms without new additional calculations. Results are…

Quantum Physics · Physics 2013-08-21 N. N. Trunov

This work presents an efficient numerical method to evaluate the free energy density and associated thermodynamic quantities of (quasi) one-dimensional classical systems, by combining the transfer operator approach with a numerical…

Numerical Analysis · Mathematics 2021-03-09 Christian B. Mendl , Folkmar Bornemann

We describe a semiclassical treatment of nuclear fusion reactions involving weakly bound nuclei. In this treatment, the complete fusion probabilities are approximated by products of two factors: a tunneling probability and the probability…

Nuclear Theory · Physics 2009-11-11 L. F. Canto , R. Donangelo , H. D. Marta

Methods based on propagation of the one-body reduced density-matrix hold much promise for the simulation of correlated many-electron dynamics far from equilibrium, but difficulties with finding good approximations for the interaction term…

Chemical Physics · Physics 2016-02-12 Peter Elliott , Neepa T. Maitra

We consider Euclidean path integrals with higher derivative actions, including those that depend quadratically on acceleration, velocity and position. Such path integrals arise naturally in the study of stiff polymers, membranes with…

Statistical Mechanics · Physics 2025-01-23 David S. Dean , Bing Miao , Rudi Podgornik

We develop a new semiclassical approach, which starts with the density matrix given by the Euclidean time path integral with fixed coinciding endpoints, and proceed by identifying classical (minimal Euclidean action) path, to be referred to…

High Energy Physics - Theory · Physics 2016-06-01 M. A. Escobar-Ruiz , E. Shuryak , A. V. Turbiner

In the present paper, we develop a semiclassical quasi-static model accounting for molecular double ionization in an intense laser pulse. With this model, we achieve insight into the dynamics of two highly-correlated valence electrons under…

Atomic and Molecular Clusters · Physics 2009-11-13 Di-Fa Ye , Jing Chen , Jie Liu

Using transfer matrix and finite-size scaling methods, we study the thermodynamic behavior of a lattice gas with two kinds of particles on the square lattice. Only excluded volume interactions are considered, so that the model is athermal.…

Statistical Mechanics · Physics 2015-09-03 T. J. Oliveira , J. F. Stilck

The matrix element method utilizes ab initio calculations of probability densities as powerful discriminants for processes of interest in experimental particle physics. The method has already been used successfully at previous and current…

Computational Physics · Physics 2015-05-20 Doug Schouten , Adam DeAbreu , Bernd Stelzer

We propose a trajectory-based quasiclassical method for approximating dynamics in condensed phase systems. Building upon the previously developed Optimized Mean Trajectory (OMT) approximation that has been used to compute linear and…

Chemical Physics · Physics 2024-08-23 Kritanjan Polley

The spectrum of eigenenergies of a quantum integrable system whose hamiltonian depends on a single parameter shows degeneracies (crossings) when the parameter varies. We derive a semiclassical expression for the density of crossings in the…

Quantum Physics · Physics 2009-10-31 A. J. Fendrik , M. J. Sánchez

The successful quasi-particle model is compared with recent lattice data of the coefficients in the Taylor series expansion of the excess pressure at finite temperature and baryon density. A chain of approximations, starting from QCD to…

High Energy Physics - Phenomenology · Physics 2009-11-10 M. Bluhm , B. Kampfer , G. Soff

A semiclassical method of complex trajectories for the calculation of the tunneling exponent in systems with many degrees of freedom is further developed. It is supplemented with an easily implementable technique, which enables one to…

Quantum Physics · Physics 2008-11-26 F. Bezrukov , D. Levkov

An $S$--matrix approach is developed for the chaotic dynamics of a nonlinear oscillator with dissipation. The quantum--classical crossover is studied in the framework of the semiclassical expansion for the $S$--matrix. Analytical…

Chaotic Dynamics · Physics 2009-11-10 A. Iomin

We apply superstatistical techniques to an experimental time series of measured transient current through a thin Aluminium-PMMA-Aluminium film. We show that in good approximation the current can be approximated by local Gaussian processes…

Statistical Mechanics · Physics 2012-01-25 G. Cigdem Yalcin , Christian Beck

Process of quantum tunneling of particles in various physical systems can be effectively controlled even by a weak and slow varying in time electromagnetic signal if to adapt specially its shape to a particular system. During an…

Quantum Physics · Physics 2009-02-05 B. I. Ivlev