Is any physical outcome 100% predictable?
If you believe in chaos theory, the answer is no. Dynamical systems are highly sensitive to initial conditions. It means that if you want to calculate the outcome of a process, you have to know the exact values of the initial conditions, and this is impossible. Initial conditions very similar, but different after all, give very different results. This is what surprised Lorentz when he discovered that slightly different initial conditions forecast very different weathers
The outcome of chaotic systems can be predicted 100%, if all the variables are known, also not all systems are chaotic.
The answer's still no though 'cos in QM the collapse of the wavefunction is a stochastic process.
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