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Related papers: Dissipation coefficients from scalar and fermion q…

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The virial expansion method is applied within a harmonic approximation to an interacting N-body system of identical fermions. We compute the canonical partition functions for two and three particles to get the two lowest orders in the…

Statistical Mechanics · Physics 2012-12-27 J. R. Armstrong , N. T. Zinner , D. V. Fedorov , A. S. Jensen

We theoretically investigate the effect of dissipation on multi-photon excitation of Rydberg atoms. The steady states and the dynamics are compared via two types of four-level excitation schemes with different dissipative paths of…

Atomic Physics · Physics 2015-06-22 Jing Qian , Weiping Zhang

In this paper, we study a warm intermediate inflationary model with a general form for the dissipative coefficient $\Gamma(T,\phi)=C_\phi\,T^{m}/\phi^{m-1}$ in the context of loop quantum cosmology. We examine this model in the weak and…

General Relativity and Quantum Cosmology · Physics 2014-09-02 Ramón Herrera , Marco Olivares , Nelson Videla

We study the thermalization of an elementary quantum system modeled by a two-level atom interacting with stationary electromagnetic fields out of thermal equilibrium near a dielectric slab. The slab is held at a temperature different from…

Quantum Physics · Physics 2016-01-20 Puxun Wu , Hongwei Yu

An intriguing phenomenon in non-equilibrium quantum thermodynamics is the asymmetry of thermal processes. Relaxation to thermal equilibrium is the most important dissipative process, being a key concept for the design of heat engines and…

Quantum Physics · Physics 2025-04-09 Álvaro Tejero , Rafael Sánchez , Laiachi El Kaoutit , Daniel Manzano , Antonio Lasanta

Picking out DBI scalar field as inflation, the slow-rolling inflationary scenario is studied by attributing an exponential time function to scale factor; known as intermediate inflation. The perturbation parameters of the model are…

General Relativity and Quantum Cosmology · Physics 2017-08-15 N. Nazavari , A. Mohammadi , Z. Ossoulian , Kh. Saaidi

We study adiabatic and isocurvature perturbations produced during a period of cosmological inflation. We compute the power spectra and cross spectra of the curvature and isocurvature modes, as well as the tensor perturbation spectrum in…

Astrophysics · Physics 2009-11-06 N. Bartolo , S. Matarrese , A. Riotto

Linearizing the appropriate kinetic equation we derive general response functions including selfconsistent mean fields or density functionals and collisional dissipative contributions. The latter ones are considered in relaxation time…

Nuclear Theory · Physics 2008-12-18 Klaus Morawetz , Uwe Fuhrmann

We study the problem of scalar particle production after inflation by a rapidly oscillating inflaton field. We use the framework of the chaotic inflation scenario with quartic and quadratic inflaton potentials. Particular attention is paid…

High Energy Physics - Phenomenology · Physics 2009-10-28 Y. Shtanov , J. Traschen , R. Brandenberger

We show that topological phases with fractional excitations can occur in two-dimensional ultracold dipolar gases on a particular class of optical lattices. Due to the dipolar interaction and lattice confinement, a quantum dimer model…

Quantum Gases · Physics 2010-04-26 Kai Sun , Erhai Zhao , W. Vincent Liu

A dissipative mechanism is presented, which emerges in generic interacting quantum field systems and which leads to robust warm inflation. An explicit example is considered, where using typical parameter values, it is shown that…

High Energy Physics - Phenomenology · Physics 2009-11-07 Arjun Berera , Rudnei O. Ramos

Warm inflation in the non minimal derivative coupling model with a general dissipation coefficient is considered. We investigate conditions for the existence of the slow roll approximation and study cosmological perturbations. The spectral…

General Relativity and Quantum Cosmology · Physics 2017-03-08 H. Mohseni Sadjadi , Parviz Goodarzi

A new approach to the dynamics of relaxation and kinetics of thermalization in a scalar field theory is presented that incorporates the relevant time scales through the resummation of hard thermal loops. An alternative derivation of the…

High Energy Physics - Phenomenology · Physics 2009-10-28 D. Boyanovsky , I. D. Lawrie , D. S. Lee

We study the effective parameters of QED near decoupling temperatures and show that the QED perturbative series is convergent, at temperatures below the decoupling temperature. The renormalization constant of QED acquires different values…

High Energy Physics - Theory · Physics 2017-04-26 Samina S. Masood

We use the quantum threshold laws combined with a classical capture model to provide an analytical estimate of the chemical quenching cross sections and rate coefficients of two colliding particles at ultralow temperatures. We apply this…

Atomic Physics · Physics 2010-02-05 Goulven Quéméner , John L. Bohn

We introduce a new theoretical approach to dissipative quantum systems. By means of a continuous sequence of infinitesimal unitary transformations, we decouple the small quantum system that one is interested in from its thermodynamically…

Condensed Matter · Physics 2016-08-31 Stefan K. Kehrein , Andreas Mielke

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

Axion-like particles with a coupling to non-Abelian gauge fields at finite temperature can experience dissipation due to sphaleron heating. This could play an important role for warm inflation or dynamical dark energy. We investigate to…

High Energy Physics - Phenomenology · Physics 2024-11-12 Marco Drewes , Sebastian Zell

We study the effect of finite temperatures and Fermion density on the effective pseudo-scalar-photon vertex induced by the triangle diagram. The manifestly covariant calculations show that when the pseudo-scalar mass is much less than the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Sourendu Gupta , S. N. Nayak

The possibility of thermally induced initial density perturbations in inflationary cosmology is examined. The fluctuation dynamics of a scalar field plus thermal bath system during slow roll is described by a Langevin-like equation.…

Astrophysics · Physics 2016-08-30 Arjun Berera , Li-Zhi Fang