Spacetime could behave like a liquid
Sheldon and Leonard's submitted theory – aptly titled The Cooper-Hofstadter paper – is all about superfluid vacuum theory, an idea that envisions a fundamental physical vacuum as a superfluid. In the science world, this idea is considered a "fringe theory," supported by only a small group of scientists. Stephen Hawking is not one of the scientists that fully backs the theory, which led him to poke fun at Sheldon and Leonard online.
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