Nonlocal gravity in a proper tetrad frame: traversable wormholes

Abstract

We investigate the revised Deser-Woodard model of nonlocal gravity involving four auxiliary scalar fields, introduced to explain the standard cosmological background expansion history without fine-tuning issues. In particular, we simplify the complex field equations within a proper tetrad frame, thereby recasting the original system into a more tractable equivalent differential problem. We show that, by initially postulating the form of the gtt metric component, it is possible to reconstruct the distortion function of the gravitational model. We then describe a step-by-step procedure for solving the vacuum field equations in the case of a static and spherically symmetric spacetime. We apply our technique to find new traversable wormholes supported purely by gravity by employing either analytical, perturbative, or numerical methods. Furthermore, we demonstrate that the role of the nonlocal effects is analogous to that of exotic matter in general relativity, owing to their quantum nature. Finally, we discuss the main geometric properties of the obtained solutions. Our results present a feasible avenue for identifying novel compact objects while enhancing the comprehension of nonlocal gravitational theories.