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PBS Space Time
What If Gravity is Not Quantum?
Season 9
Episode 30
The holy grail of theoretical physics is to come up with a quantum theory of gravity. But after a century of trying we really have no idea how close we are, or it it's even possible. But we shouldn't feel bad because it turns out that the universe is doing everything it its power to make this as difficult as possible. Or it's telling us that it isn't. Should we take the hint?
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