Well, the very short answer that I've arrived is that: If you believe in the Copenhagen interpretation (and similar interpretations) then the universe isn't de

Well, the very short answer that I've arrived is that: If you believe in the Copenhagen interpretation (and similar interpretations) then the universe isn't deterministic - there are many events that can happen but only one does happen in the end (when the set of probabilities assume specific values - the wavefunction collapse). If you subscribe to the Many-worlds Interpretation then the universe is deterministic in a way - all events that could happen will happen in some branches (or in a portion of the branches equal to the probability of the event happening, as much as this makes sense) and it was all going to be that way since 'the beginning of time'. However, from another point of view (ours) - it isn't determined which branch you will experience yourself observing and this can make things seem non-deterministic (but in reality you or equivalents of you will experience yourself observing all branches in which you exist so I don't think that this would be the correct way to think about it).