Description
The Born-Infeld gravity is a modified gravity motivated by the quantum gravity, which has the ability to get rid of the Big Bang and other singularities. The action is highly non-linear, and the ghost mode appears in the metric formalism although we can show that the ghost mode does not appear in the Palatini formalism. We investigate the FLRW universe with dust in this theory, and show that the Big Bang singularity does not always emerge but the scale factor can be bounced. Based on this result, we also discuss the black hole formation for spherical dust collapse.