Thanks to all the replies so far, I'm beginning to get a better idea of where we stand.
One thing though, why is the idea I originally had a hidden variables theory which falls foul of Bell's theorem ( which I think I understand ). In my original post, the universe is completely deterministic...
I'm trying to at least understand what decoherence can and cannot explain about how quantum mechanics works, the more I read, the less clear I am about what is known and what is merely speculative.
So I finally decided the only way to get any further was to try and clarify what I think is...