Ok expanding on my first post.
The idea is completely absurd, because nothing the world really is random. If you know every part of what goes into determining something, then you too can know the outcome.
I tried to explain in my first post that no, if you know what goes into something, it doesn't meant that you will know what comes out.
In computing the Halting Problem specifically addresses this. You have a description of a program which solves a specific problem. On the correct answer it halts, on a incorrect answer it carries on forever.
Now take this program and feed it into a general machine which halts on an incorrect answer and carries on forever on a correct answer.
When do you know that the program has finished, or when it has failed? In other words even though you know the input, you can't say what the output is.
Also in my previous argument I've also stated that for one input you could can get more than one answer.
Another problem is N=NP. It boils down simply needing to have a non-deterministic computer to be able to solve a set of problems called NP. (Ok this hasn't strictly true, but having a problem which takes longer than the life span of the universe to run through is a little unpractical.) Calculating the universe would fall into this set of problems NP. To calculate it a quantum computer is required.
But you start getting into problem with quantum that when you observe or measure the results that it can change the outcome. Whose to say that predicting the future on your quantum computer isn't going to change the prediction?
Parallel World. What I hate, HATE is that people thing parallel words can only made by a choice or a decision. If the point of a parallel universe is that it is DIFFERENT from ours, then image a universe that is exactly the same as ours in all respects. Everything, but one tiny atom, which for a fraction of second vibrates slightly differently, but then goes back to being the same as ours.
Superficially it's the same, except for this one action and this one point of time. Then image this happens for each atom, in each possible point of time, then you start taking combinations of atoms and they start vibrating and as you can see there is all ready going to be an infinite amount of universes which LOOK EXACTLY LIKE OURS!
So we have an infinite amount of infinite universes.
Is free will a sham? Is everything pre-determined? No, I don't believe so, and there are plenty of different problems in plenty of different fields to prove this. I've given some, and some other people have given some.
As for a free will being your 'soul '? Free will doesn't prove or disprove that you have a soul, just that you have free will.
I think I have to much free time on my hands.