Propriedades de objetos compactos regulares na relatividade geral e teorias modificadas de gravitação

Abstract

In this work, we investigate the properties of regular compact objects in the context of both general relativity and modified theories of gravity, with emphasis on wormholes, black bounce geometries, and solutions in f(R) gravity. We begin by studying the geometric properties and the field sources associated with two wormhole models: (i) a generalization of the Ellis-Bronnikov solution and (ii) a new model that admits multiple throats and anti-throats, discussing their physical features and causal structure. Next, we explore how the Simpson-Visser metric - and, more generally, other regular geometries whose sources are well-defined in general relativity - can be reinterpreted as viable solutions in f(R) gravity, by identifying the necessary corrections in the corresponding field equations. Finally, in the context of black bounce geometries, we analyze the effects of tidal forces in different spacetimes, highlighting how these structures can, in principle, be distinguished from classical black holes through physical observables.