English
Related papers

Related papers: Fermion Damping in a Fermion-Scalar Plasma

200 papers

The motion of a scalar field that interacts with a hot plasma, like the inflaton during reheating, is damped, which is a dissipative process. At high temperatures the damping can be described by a local term in the effective equation of…

High Energy Physics - Phenomenology · Physics 2022-10-05 Dietrich Bodeker , Jan Nienaber

For short wavelengths, it is well known that the linearized Wigner-Moyal equation predicts wave damping due to wave-particle interaction, where the resonant velocity shifted from the phase velocity by a velocity $v_q = \hbar k/2m$. Here…

Plasma Physics · Physics 2017-11-15 Gert Brodin , Robin Ekman , Jens Zamanian

We determine the dispersion relations of fermionic quasiparticles in ultradegenerate plasmas by a complete evaluation of the on-shell hard-dense-loop-resummed one-loop fermion self energy for momenta of the order of the Fermi momentum and…

High Energy Physics - Phenomenology · Physics 2009-11-11 A. Gerhold , A. Rebhan

We consider a model with global Abelian chiral symmetry of two massless fermion fields interacting with a complex massive scalar field. We argue that the Schwinger-Dyson equations for the fermion and boson propagators admit…

High Energy Physics - Phenomenology · Physics 2007-05-23 Tomas Brauner , Jiri Hosek

We investigate an inflationary model wherein the Dirac field $\psi$ is directly coupled to a scalar inflaton $\phi$ via a Yukawa interaction $g\phi\bar\psi\psi$ and examine the resulting observational implications. Within the slow-roll…

General Relativity and Quantum Cosmology · Physics 2025-10-20 Lin-Hong Sui , Dan Li , Jia-Ze Sun , Xi-Bin Li

We study the one-loop radiative corrections for massless fermions in de Sitter space induced by a Yukawa coupling to a light, nearly minimally coupled scalar field. We show that the fermions acquire a mass. Next we construct the…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Bjorn Garbrecht , Tomislav Prokopec

A new formulation of perturbation theory for a description of the Dirac and scalar fields (the Yukawa model) is suggested. As the main approximation the self-consistent field model is chosen, which allows in a certain degree to account for…

General Physics · Physics 2016-06-01 Yu. M. Poluektov

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

Motivated by apparent persistent large scale anomalies in the CMB we study the influence of fermionic degrees of freedom on the dynamics of inflaton fluctuations as a possible source of violations of (nearly) scale invariance on…

General Relativity and Quantum Cosmology · Physics 2016-04-20 Daniel Boyanovsky

: We examine again the problem of the damping rate of a moving heavy fermion in a hot plasma within the resummed perturbative theory of Pisarski and Braaten. The ansatz for its evaluation which relates it to the imaginary part of the…

High Energy Physics - Phenomenology · Physics 2009-10-22 S. Peigne , E. Pilon , D. Schiff

We non-perturbatively study the fermion spectrum in the chiral symmetric phase from the Schwinger-Dyson equation with the Feynman gauge, in which we perform an analytic continuation of the solution on the imaginary time axis to the real…

High Energy Physics - Phenomenology · Physics 2008-01-24 Masayasu Harada , Yukio Nemoto , Shunji Yoshimoto

We construct the propagator for a free fermionic unparticle field from basic considerations of scale and Lorentz invariance. The propagator is fixed up to a normalization factor which is required to recover the result of a free massless…

High Energy Physics - Phenomenology · Physics 2008-11-26 Yi Liao

We study a system of fermions interacting with a scalar field, in 4+1 dimensions where the 5th dimension is compactified, using an exact functional method, where quantum fluctuations are controlled by the amplitude of the bare fermion mass.…

High Energy Physics - Phenomenology · Physics 2009-11-11 Jean Alexandre , Konstantinos Farakos

We propose a mass-varying dark matter (MVDM) model consisting of a scalar field and a fermionic field interacting via a simple Yukawa coupling, and containing an exponential self-interaction potential for the scalar field. Analyzing the…

High Energy Physics - Phenomenology · Physics 2024-02-06 Sayan Mandal , Neelima Sehgal

Two fermions occupying the same site of a lattice model with strongly repulsive Hubbard-type interaction U form a doublon, a long-living excitation the decay of which is suppressed because of energy conservation. By means of an…

Quantum Gases · Physics 2012-05-16 Felix Hofmann , Michael Potthoff

We review the non-Fermi or marginal liquid behavior of a relativistic QED plasma. In this medium a quasiparticle has a damping rate that depends linearly on the distance between its energy and the Fermi surface. We stress that this…

High Energy Physics - Phenomenology · Physics 2017-08-23 Cristina Manuel

We present results for the fermion determinant in an external Yukawa-coupled scalar field, a quantity relevant to instanton and sphaleron transition rates as well as bubble nucleation occuring in the electroweak phase transition when the…

High Energy Physics - Phenomenology · Physics 2009-10-28 J. Baacke , H. So , A. Suerig

We reinvestigate the interaction of massless fermions with massless bosons at finite temperature. Specifically, we calculate the self-energy of massless fermions due the interaction with massless bosons at high temperature, which is the…

High Energy Physics - Phenomenology · Physics 2015-06-25 H. C. de Godoy Caldas

The decay of a heavy neutral scalar particle into fermions and into charged scalars are analyzed when in the presence of an external magnetic field and finite temperature. Working in the one-loop approximation for the study of these decay…

High Energy Physics - Phenomenology · Physics 2018-10-24 Aritra Bandyopadhyay , Ricardo L. S. Farias , Rudnei O. Ramos

We study the production of fermions through a derivative coupling with a pseudoscalar inflaton and the effects of the produced fermions on the scalar primordial perturbations. We present analytic results for the modification of the scalar…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-18 Peter Adshead , Lauren Pearce , Marco Peloso , Michael A. Roberts , Lorenzo Sorbo