Live Science spoke with Nobel prize-winning physicist David Gross, who recently received the $3 million Special Breakthrough Prize in Fundamental Physics, about the quest to unite all the forces and why humanity might not live to see a unified theory.
Regardless of nuclear war, having a theory of quantum gravity is looking unlikely in this century. The conditions needed to run useful experiments are far beyond the capabilities of human engineering. Without experimental data to constrain the theory, we’re going to be perpetually stumped messing about with math and making claims about quantum gravity in universes that are not our own.
The problem is similar in scale to trying to derive quantum field theory from Newtonian physics without having electricity or advanced metallurgy.