The new proof establishes that quantum computers that calculate with entangled quantum bits or qubits, rather than classical 1s and 0s, can theoretically be used to verify answers to an incredibly vast set of problems. The correspondence between entanglement and computing came as a jolt to many researchers.

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When problems are relatively simple, you can check the answer yourself. But when they get more complicated, even checking an answer can be an overwhelming task. However, in 1985 computer scientists realized its possible to develop confidence that an answer is correct even when you cant confirm it yourself.

Source: Landmark Computer Science Proof Cascades Through Physics and Math - Quanta Magazine

I remember wondering about this when I read about quantum physics recently (in Quantum Physics for Babies, of all things). Certainly not in as much detail as these researchers did, but it’s very interesting that just a number of months later this proof was published. I’m honestly still digesting it.