Bounce models within teleparallel modified gravity
Alessandro Casalino, Bruno Sanna, Lorenzo Sebastiani, Sergio Zerbini
Abstract
In this paper, working in a Friedman-Lemaitre-Robertson-Walker (FLRW) space-time, we recover, without invoking unconventional exotic matter, the generalized Friedman equation of quantum loop cosmology, and therefore the cosmological bounce. We obtain this result proposing a new model in the framework of modified teleparallel gravity, where the Ricci scalar is replaced by the torsion scalar $T$. Furthermore we show that the associated perturbations again in a flat FLRW space-time are not affected by superluminarities or gradient instabilities. Then, we generalize the results to the curved FLRW space-time by using an appropriate formulation. In this context, the results of the Born-Infeld model are also investigated.