Searcharxiv⌕ Search

arXiv subjects

H. C. de Godoy Caldas

Publications and source records attributed to H. C. de Godoy Caldas.

5 recordsLinked to original sources
arXiv2003

Analytic Properties of Thermal Corrected Boson Propagators

We investigate the analytic properties of finite-temperature self-energies of bosons interacting with fermions at one-loop order. A simple boson-fermion model was chosen due to its interesting features of having two distinct couplings of bosons with fermions. This leads to a quite different analytic behavior of the bosons self-energies as the external momentum $K^μ=(k^{0},\vec{k})$ approaches zero in the two possible limits. It is shown that the plasmon and Debye masses are consistently obtained at the pole of the corrected propagator even when the self-energy is analytic at the origin in the frequency-momentum space.

hep-ph↗
arXiv2002

Symmetry Nonrestoration in a Resummed Renormalized Theory at High Temperature

We reinvestigate the interesting phenomenon of symmetry nonrestoration at high temperature in the multifield O(N_1) X O(N_2) model. We apply modified self-consistent resummation (MSCR) in order to obtain the scalar dressed masses and find in what circumstances a resummed multifield theory which has symmetry (non)restoration can be renormalized. It is shown that, aside from the consistency of the MSCR method, the basic ingredient that guarantees the renormalization of a multifield model within a resummation approach is the T^2 mass behavior of field theory at high temperature.

hep-ph↗
arXiv2002

Dressing a Scalar Mass up to Two-Loop Order at Finite Temperature

In this paper we use Modified Self-Consistent Resummation (MSCR) in order to obtain the scalar dressed mass by evaluating the self-energy up to two loops in the neutral scalar $λϕ^4$ model at finite temperature. With this laboratory model we show that, if a theory is renormalizable at zero temperature, using the MSCR it is always possible to obtain a finite corrected mass at finite temperature. This feature of the MSCR is not observed in some other approximation techniques usually found in the literature.

hep-th↗
arXiv2001

The Fermion Boson Interaction Within the Linear Sigma Model at Finite Temperature

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 region where thermal effects are maximal. The calculations are concentrated in the limit of vanishing fermion three momentum and after considering the effective fermion and boson dressed masses, we obtain the damping rate of the fermion up to order $g^3$. It is shown that in the limit $k_0 \ll T$ the fermion acquire a thermal mass of order $gT$ and the leading term of the fermion damping rate is of order $g^2T+g^3T$.

hep-ph↗