>>7613969The answet to that question is under debate, and might never be answered.
The closest we can get to an answer right now is, "everything we can observe suggests that this is so."
There is still philosophical wiggle-room, however, which lies in asking whether the randomness of quantum effects, which has been proven to be fundimental, and not merely unknown due to insufficent measurement, might nevertheless be "fated" to occur, in some way not perceptable from within the universe.
For example, consider the following thought experiment: a single radioactive isotope will either decay in a given span of time, ir won't. This cannot be predicted; its probability can be calculated, but that's it.
Suppose that we wait until it does decay, which we are able to detect in sone way, and mark the time.
If we had access to a time machine that let us go back to before the isotope decayed, and we sat around until the moment we previosly recorded arrived, would the isotope decay at that same moment? We have no access to time machines, so it is a pointless, meaningless scenario, but it does expose our intuition about the dynamics of the universe.
If you believe that the isotope would decay the same as before, then you believe that there is some sort of fate, governing even that which is proven to be truly random. If you believe it would decay at a different time, then the many-worlds interpretation may appeal to you. Lastly, if you refuse to consider the scenario until we have access to time machines, then you are a much better scientist than I.
...but much less fun, too.
