Even more problematic is that we can’t even predict what a merged theory of quantum gravity would look like. Physicists have often been able to predict particles that were later discovered experimentally (like the top quark or the Higgs boson), but so far all the theories we have that try to merge gravity and quantum mechanics fail; they keep giving nonsense results, like “infinity.” Theorists are a smart bunch (in theory), and they have some good ideas that might one day lead to a merged theory—such as string theory or loop quantum gravity—but it’s fair to say that to date the progress has
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