Bell's theorem.


John Stewart Bell's inequality showed that there's no way a theory with local hidden variables could reproduce QM's predictions. So, in order to match QM's predictions, any theory has to discard local reality. Then, according to Bell, we only have two ways to explain QM's weirdness: faster than light communication or superdeterminism.

Bell, like Einstein, didn't realize reality is extremely different at the speed of light. Entities that travel at c don't need predictive superpowers, retroactive signalling or predestination to know what will happen to them because they are able to “compress” any spacetime interval into an instantaneous event. Our reality is, then, recreated each time by detecting those exchanges, so it's no surprise we can detect hints of weird connections across space, when spacetime structure itself emerges from the immense number of correlated connections that develop each time. Spacetime behaves like a quantum error-correction algorithm, where anything that happens keeps consistency with everything else that is directly related to it.

SR showed space and time depend on motion, but it also shows determinism and locality disappear at the speed limit. We always take our material world experience (causality and locality) as the correct point of view, while we should also take into account how carriers experience existence (instantaneity and entanglement). Any interaction that happens in the universe complies with this dual nature of reality.

If time is meaningless for things that go at c, then properties can't have specific values “before” measurement. In the same way, if distance is meaningless for things that go at c, then what's the difference between a local or nonlocal thing? For a force carrier, our spacetime interval is localized at its point-instant, so who contains who? Is a photon from the sun really travelling through space to our eye at c? Or is that spacetime interval the only way we have to understand that a sun-eye interaction took place?

0 comments:

Post a Comment