Quantum Gravity

This is the Holy Grail of Theoretical Physics. Without experimental guidance it has been difficult to find out the right theory. Recently there are two reports that make me think that some progress lies around the corner.

Photons produced at the same time in the same place got to Earth a few minutes apart due to energy differences

Black holes produced at the LHC in Switzerland next year will mainly decay in known particles

The second observation explains why gravity is so weak, and consequently why the repulsive negative energy of the Universe is so little. The first observation can be understood, introducing a smallest size in the Universe, the Planck size.

In any case the Quantum Gravity conundrum goes to the very essence of existence. Not only why are we here, but also, and maybe more importantly, How does the Universe behave?