Regular black hole interior solutions in classical gravity violating Penrose’s energy conditions
General Relativity and Penrose’s singularity theorems directly point towards the solution to gravitational singularities at back hole interiors in a classical way through negative masses violating energy conditions. This implies a mechanism to switch from positive to negative masses and energies at the event horizon, which is thought to be a time transformation. The solution to geodesic incompleteness in black holes is an open problem which could hint a more complete theory of gravity and explain the nature of time.