Do we actually live in a deterministic Universe, despite quantum physics? An alternative, non-spooky interpretation has now been ruled out.
For all of history, there’s been an underlying but unspoken assumption about the laws that govern the Universe: that if you know enough information about a system, like the positions, momenta, and properties of the particles within it, then you can use that information to predict precisely how that system will evolve and behave in the future. The assumption is, in other words, that the equations governing the Universe are deterministic. The classical equations of motion — Newton’s laws — are completely deterministic. The laws of gravity, both Newton’s and Einstein’s, are deterministic. Even Maxwell’s equations, governing classical electricity and magnetism, are 100% deterministic as well.
But that picture of the Universe got turned on its head with a series of discoveries that began in the late 1800s. Starting with radioactivity and radioactive decay, humanity slowly uncovered aspects about the nature of reality that were fundamentally quantum, casting doubt on the idea that we live in a deterministic Universe. In terms of predictive power, many aspects of reality could only be discussed in a…