So a few months ago a research team did the following experiment: https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.118.060401
They shot lasers at certain detectors trying to detect the spin of the photons and to prove that there is an underlying hidden variable that influences all of these properties, for which quantum entanglement exists. The measurement of the spin depends on the orientation of the detector. To each detector is a telescope attached and pointing to a 600ly distant star. And based on the wavelengths of the photons that hit the telescope, the detector is reoriented.
So now my question is, is this really random? I mean yes, the photons from the sun were created even before the laser were set up. But since we live all in the same universe, nothing is really COMPLETELY random, just to a certain degree. Isn't bells theorem even a proof that causality doesn't even exist at a certain degree or that true randomness doesn't exist?