Decaimento de fótons no modelo padrão estendido

Abstract

The discovery of Lorentz symmetry was one of the great advances in modern physics. This symmetry has been increasingly confirmed by various experiments over the past few decades. Thus, a search for small deviations from this symmetry is a window to search for a new physics. The present work is dedicated to photon decay, in the context of the Standard-Model Extension (SME). To develop this subject matter, we initially carried out a literature survey on the Lorentz noninvariant extension of the Standard Model, the well-known SME. Next, we present the characteristics of the photon sector of the SME, such as the Lagrangian, the equation of motion and its solutions, as well as the conservation laws. Later, we discuss photon decay as a consequence of a violation of Lorentz symmetry. We analyze photon decay for a particular type of violation, known as isotropic. Such a violation is obtained from the CPT-even sector of the SME. Furthermore, we discuss some classical and quantum aspects of the isotropic sector of the modified electromagnetic theory and obtain a series of results related to the photon decay process. The fact that photon decay has not been observed in any experiment allows us to set limits on the isotropic coefficient.