Eddington-inspired Born-Infeld gravity: nuclear physics constraints and the validity of the continuous fluid approximation

Understand

In this paper we investigate the classical non-relativistic limit of the Eddington-inspired Born-Infeld theory of gravity.

• We show that strong bounds on the value of the only additional parameter of the theory \kappa, with respect to general relativity, may be obtained by requiring that gravity plays a subdominant role compared to electromagnetic interactions inside atomic nuclei.
• We also discuss the validity of the continuous fluid approximation used in this and other astrophysical and cosmological studies.
• We argue that although the continuous fluid approximation is expected to be valid in the case of sufficiently smooth density distributions, its use should eventually be validated at a quantum level.