Infrared lessons for ultraviolet gravity: the case of massive gravity and Born-Infeld

Article Article scientifique Article Infrared lessons for ultraviolet gravity: the case of massive gravity and Born-Infeld eng 2014 author Beltran Jimenez José 727055 author Heisenberg Lavinia 714549 author Olmo Gonzalo J. 004 10.1088/1475-7516/2014/11/004 1475-7516 1409.0233 We generalize the ultraviolet sector of gravitation via a Born-Infeld action using lessons from massive gravity. The theory contains all of the elementary symmetric polynomials and is treated in the Palatini formalism. We show how the connection can be solved algebraically to be the Levi-Civita connection of an effective metric. The non-linearity of the algebraic equations yields several branches, one of which always reduces to General Relativity at low curvatures. We explore in detail a minimal version of the theory, for which we study solutions in the presence of a perfect fluid with special attention to the cosmological evolution. In vacuum we recover Ricci-flat solutions, but also an additional physical solution corresponding to an Einstein space. The existence of two physical branches remains for non-vacuum solutions and, in addition, the branch that connects to the Einstein space in vacuum is not very sensitive to the specific value of the energy density. For the branch that connects to the General Relativity limit we generically find three behaviours for the Hubble function depending on the equation of state of the fluid, namely: either there is a maximum value for the energy density that connects continuously with vacuum, or the energy density can be arbitrarily large but the Hubble function saturates and remains constant at high energy densities, or the energy density is unbounded and the Hubble function grows faster than in General Relativity. The second case is particularly interesting because it could offer an interesting inflationary epoch even in the presence of a dust component. Finally, we discuss the possibility of avoiding certain types of singularities within the minimal model. Alternatives to inflation Gravity Modified gravity Dewey 500.2 Open Access - SCOAP3 34 Département de physique nucléaire et corpusculaire 132 false Journal of cosmology and astroparticle physics 1411 11 b10d4968-ff8c-4650-a221-d4432007354e Article (Published version) Public fulltext.pdf 558908 application/pdf CC BY openAccess Faculté des sciences / Section de physique / Département de physique nucléaire et corpusculaire

Title	Published in	Access level	OA Policy	Year	Views	Downloads

Infrared lessons for ultraviolet gravity: the case of massive gravity and Born-Infeld	Journal of cosmology and astroparticle physics			2014	586	416

Archive ouverte UNIGE

Beltran Jimenez, José