Related papers: On the higher-loop effective action in NJL model
Recently, it has been shown that the standard Nambu-Jona-Lasinio (NJL) model is not able to reproduce the correct QCD behavior of the gap equation at large density, and therefore a different cutoff procedure at large momenta has ben…
The one-loop low-energy effective action for non-Abelian N=4 supersymmetric Yang-Mills theory is computed to order $F^6$ by use of heat kernel techniques in N=1 superspace. At the component level, the $F^5$ terms are found to be consistent…
Transport theory for the Nambu--Jona-Lasinio (NJL) model is examined. The collision term is investigated in a first approach in a coupling strength expansion. It can be demonstrated that this leads to a form easily recognized from the…
We discuss the phase structure of the NJL model in curved spacetime with magnetic field using $1/N$-expansion and linear curvature approximation. The effective potential for composite fields $\bar\psi \psi$ is calculated using the…
We present a study of correlations among conserved charges like baryon number, electric charge and strangeness in the framework of 2+1 flavor Polyakov loop extended Nambu-Jona-Lasinio model at vanishing chemical potentials, up to fourth…
The branching fraction of the decay $\tau \to K^{-} K^{0} \nu_{\tau}$ is calculated in the framework of the extended Nambu--Jona-Lasinio model. The contact and vector channels are considered. The contributions to this process of the $\rho$…
The electric polarizability of the nucleon is calculated in the soliton approach to the Nambu--Jona-Lasinio model. We analyze the leading-$N_c$ contributions, as well as the effects of rotational $1/N_c$ corrections and $\Delta$-$N$ mass…
A detailed study of the 4He longitudinal response function R_L(\omega,q) is performed at different kinematics, with particular emphasis on the role of three-nucleon forces. The effects shown are the results of an ab initio calculation where…
We study the problem of triviality in the four dimensional Nambu-Jona-Lasinio model with discrete chiral symmetry using both large-N expansions and lattice simulations. We find that logarithmic corrections to scaling appear in the equation…
We calculate the one-loop contributions to the tau slepton masses in the Minimal Supersymmetric Standard Model in the effective potential approach. For the majority of parameter space under study, those corrections are shown to elevate the…
The behavior of charged and neutral pion masses in the presence of a static uniform magnetic field is studied in the framework of the two-flavor Nambu-Jona-Lasinio (NJL) model. Analytical calculations are carried out employing the Ritus…
We present master formulas for the divergent part of the one-loop effective action for a minimal operator of any order in the 4-dimensional curved space and for an arbitrary nonminimal operator in the flat space.
The possibility to use the width of the decay $\rho \to e^{+}e^{-}$ to fix the input parameter $g_\rho=5.0$ of the $SU(2) \times SU(2)$ chiral-symmetric Nambu--Jona-Lasinio model is discussed. It is shown that for a consistent simultaneous…
In the leading order of a modified 1/Nc expansion, we show that a class of gauge-Higgs-Yukawa systems in four dimensions give non-trivial and well-defined theories in the continuum limit. The renormalized Yukawa coupling y and the quartic…
We calculate explicitly the one-loop effective potential in different Lorentz-breaking field theory models. First, we consider a Yukawa-like theory and, then, some examples of Lorentz-violating extensions of scalar QED. We observed, for the…
We apply heat kernel techniques in N=1 superspace to compute the one-loop effective action to order $F^5$ for chiral superfields coupled to a non-Abelian super Yang-Mills background. The results, when combined with those of hep-th/0210146,…
This talk describes the work done in calculating leading logarithms in massive effective field theories. We discuss shortly leading logarithms in renormalizable theories and how they can be calculated using only one-loop calculations in…
Topcolor and topcolor-assisted technicolor provide examples of dynamical electroweak symmetry breaking which include top-condensation, thereby naturally incorporating a heavy top quark. In this note we discuss the roles of the…
We discuss the limitations of the covariant derivative expansion prescription advocated to compute the one-loop Standard Model (SM) effective lagrangian when the heavy fields couple linearly to the SM. In particular, one-loop contributions…
Temperature dependence of the quark condensate is studied in the Nambu--Jona-Lasinio model with meson loops. Substantial differences are found compared to the results with quark loops only.