"I think that, without experimental checks, physics can — and has — gone off the rails ... experiment has to be the ultimate decider of what is good physics."

“Is our universe fundamentally a mess, or is there some simple and natural structure that all this could emerge from, or be parts of? One approach to answering these questions is String Theory , but string unification models have grown excessively in complexity while producing zero predictive progress. After several decades of extensive theoretical exploration leading nowhere, it is time to consider that the string program may have been a wrong turn. If we backtrack, imagining String Theory never happened, we can go in a new direction, building on the success of Grand Unified Theories and recent progress in Loop Quantum Gravity. The structures of GUTs and LQG rely heavily on Lie groups and are remarkably compatible. By considering the known Lie groups and fields of physics as parts of a larger geometric whole, we move towards Lie group unification.”