Quantum mechanics and general relativity don’t fit together, and a big part of the issue comes down to gravity. For decades, the accepted route to an ultimate theory of everything has involved taking our best theory of gravity and squeezing it into the frame of quantum mechanics. Yet, almost a century later, scientists still haven’t managed to make gravity fit. Ivette Fuentes is a professor of quantum mechanics who conducts experiments at the scales where quantum theory and general relativity interplay. Fuentes sat down with Â鶹´«Ã½ features editor Thomas Lewton to discuss the issues and fascinating theories that pop out when we try to fit classical and quantum mechanics together.

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