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Related papers: Effective actions at finite temperature

200 papers

Application of the effective action approach to amplitudes with loop integration is studied for collisions on two and three centers with possible gluon emission. A rule is formulated for the integration around pole singularities in the…

High Energy Physics - Phenomenology · Physics 2015-06-18 M. A. Braun , S. S. Pozdnyakov , M. Yu. Salykin , M. I. Vyazovsky

For quantum fermion problems, many accurate solvers are limited by the temperature regime in which they can be usefully applied. The Mermin theorem implies the uniqueness of an effective potential from which both the exact density and free…

Chemical Physics · Physics 2018-09-12 Justin Clifford Smith , Kieron Burke

We use molecular dynamics simulations to study the dynamics of an ensemble of interacting self-propelled semi-flexible polymers in contact with a thermal bath. Our intention is to model complex systems of biological interest. We find that…

Soft Condensed Matter · Physics 2011-05-06 Davide Loi , Stefano Mossa , Leticia F. Cugliandolo

Models incorporating moderately heavy dark matter (DM) typically need charged (scalar) fields to establish admissible relic densities. Since the DM freezes out at an early epoch, thermal corrections to the cross sections can be important.…

High Energy Physics - Theory · Physics 2019-06-11 Pritam Sen , D. Indumathi , Debajyoti Choudhury

The methods of quantum field theory are widely used in condensed matter physics. In particular, the concept of an effective action was proven useful when studying low temperature and long distance behavior of condensed matter systems. Often…

Strongly Correlated Electrons · Physics 2017-08-25 Alexander G. Abanov

We examine finite temperature perturbation theory for Chern-Simons theories, in the context of an analogue 0+1-dimensional model. In particular, we show how nonextensive terms arise in the perturbative finite temperature effective action,…

High Energy Physics - Theory · Physics 2009-10-30 Ashok Das , Gerald Dunne

Perturbation theory is an important tool to describe the properties of QCD at very high temperatures. Recently a new technique has been proposed to compute the one-loop effective action of QCD at finite temperature by making a gauge…

High Energy Physics - Phenomenology · Physics 2009-11-10 E. Megias

We compute the effective actions for the 0+1 dimensional scalar field interacting with an Abelian gauge background, as well as for its supersymmetric generalization at finite temperature.

High Energy Physics - Theory · Physics 2016-08-25 J. Barcelos-Neto , Ashok Das

The equations for the QED effective action derived in \cite{fm} are considered using singular perturbation theory. The effective action is divided into regular and singular (in coupling constant) parts. It is shown that expression for the…

High Energy Physics - Theory · Physics 2019-09-04 Biruniy Fayzullaev

We derive the one-loop effective action for scalar, pseudoscalar, and electromagnetic fields coupled to a Dirac fermion in an extension of QED with Yukawa couplings. Using the Schwinger proper-time formalism and zeta-function…

High Energy Physics - Theory · Physics 2018-09-20 Theodore N. Jacobson , Tonnis ter Veldhuis

Using only global symmetries of QCD, we set up an effective model of quarks at finite temperature near the cross over, including all possible terms up to dimension 6. We first treat this in mean field theory. Then we investigate low-energy…

High Energy Physics - Phenomenology · Physics 2018-03-07 Sourendu Gupta , Rishi Sharma

In this paper, we give a simple diagrammatic identification of the unique combination of the causal n-point vertex functions in the real time formalism that would coincide with the corresponding functions obtained in the imaginary time…

High Energy Physics - Theory · Physics 2016-08-25 F. T. Brandt , Ashok Das , J. Frenkel , A. J. da Silva

We analyze and give explicit representations for the effective abelian vector gauge field actions generated by charged fermions with particular attention to the thermal regime in odd dimensions, where spectral asymmetry can be present. We…

High Energy Physics - Theory · Physics 2008-11-26 S. Deser , L. Griguolo , D. Seminara

We derive finite temperature time-dependent effective actions for the phase of the pairing field, which are appropriate for a 2D electron system with both non-retarded d- and s-wave attraction. As for s-wave pairing the d-wave effective…

Superconductivity · Physics 2008-12-18 Sergei G. Sharapov , Hans Beck , Vadim M. Loktev

We consider transformations of the $2\times2$ propagator matrix in real-time finite-temperature field theory, resulting in transformed $n$--point functions. As special cases of such a transformation we examine the Keldysh basis, the…

High Energy Physics - Phenomenology · Physics 2009-10-28 M. A. van Eijck , R. Kobes , Ch. G. van Weert

Through the application of the thermal operator to the zero temperature retarded Green's functions, we derive in a simple way the well known hard thermal effective action in QCD. By relating these functions to forward scattering amplitudes…

High Energy Physics - Theory · Physics 2008-11-26 Ashok Das , J. Frenkel

The parity-violating topological term in the effective action for 2+1 massive fermions is computed at finite temperature in the presence of a constant background field strength tensor. Gauge invariance of the finite-temperature effective…

High Energy Physics - Theory · Physics 2009-10-30 R. Gonzalez Felipe

The heat kernel expansion for field theory at finite temperature is constructed. It is based on the imaginary time formalism and applies to generic Klein-Gordon operators in flat space-time. Full gauge invariance is manifest at each order…

High Energy Physics - Phenomenology · Physics 2008-11-26 E. Megias , E. Ruiz Arriola , L. L. Salcedo

We derive a general effective action for quark matter at nonzero temperature and/or nonzero density. For this purpose, we distinguish irrelevant from relevant quark modes, as well as hard from soft gluon modes by introducing two separate…

Nuclear Theory · Physics 2014-11-18 Philipp T. Reuter , Qun Wang , Dirk H. Rischke

We derive an effective theory for dense, cold and massive quark matter. To this end, we employ a general effective action formalism where antiquarks and quarks far from the Fermi surface, as well as hard gluons, are integrated out…

Nuclear Theory · Physics 2008-11-26 Philipp T. Reuter