Are our lives completely predetermined?

[Could_Strife007]

Originally Posted by Kit-

Heisenberg's Uncertainty Principle states that the product of the uncertainties which result from measuring position and momentum by any method must be greater or equal to half of Dirac's constant, meaning that it's not even potentially possible to predict their motions exactly.

OK, this page helped me understand the premise behind the Uncertainty Principle, but I'm not exactly sure why the deviation product in this case must be at least half of Dirac's constant. Why is this?

Originally Posted by Kit-

That was just experimental evidence in case people decided to say "lol heisenberg what a load of bunk."

In the sense that the experiment could only produce a function of probability?

Originally Posted by wikipedia

In classical physics, it was believed that if one knew the initial state of a system with infinite precision, one could predict the behavior of the system infinitely far into the future. According to quantum mechanics, however, there is a fundamental limit on the ability to make such predictions, because of the inability to collect the initial data with unlimited precision.

Even if there is a limit on the ability to collect the initial position, the initial position must still exist. Does Quantum Mechanics say that everything exists in multiple positions in space at one time?