Unifying quantum mechanics with general relativity is the ultimate dream — or nightmare — of physics. It would be a way to finally describe the force of gravity with the tools of quantum mechanics, unlocking how gravity works when it's really strong and at really small scales.
Einstein's theory of general relativity tells us that the warping of space and time is what we experience as the force of gravity. Quantum mechanics tells us that what we experience as the forces of nature really come in discrete, tiny chunks, known as quanta.
So, if gravity is the bending of space-time, gravity is a force and all forces are quantized, maybe space-time itself comes in discrete little blocks. Maybe there are fundamental units of space-time at some unfathomably tiny scale.
Welcome to the theory of loop quantum gravity.
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