Quebra dinâmica de simetria de Lorentz em teorias de quatro férmions

Abstract

In this master’s thesis we study the dynamically induced Lorentz symmetry breaking in four-fermion self-interecting models with and without mass. In the massive model we investigate the effective potential using the naive and the ’t Hooft-Veltman dimensional regularization methods, that will lead to different gap equations and in the second case it will create a potential that conserves the Lorentz invariance. To the massless model we use again the ’t Hooft-Veltman prescription and calculate the vacuum expectation value of the field in the contexts of zero and finite temperature. With this we show a unpublished result which reveals that, for the temporal part of , there is a temperature critical value from which the symmetry of the system is restored.