I was wondering…is there a body of evidence concerning the nature of the future, that is, is there an infinite multitude of possible futures, or just one?
Furthermore, how would conclusive proof bear upon our current knowledge of physics(relativity, quantum mechanics).
No.
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We’d finally be able to build a working flux capacitor.
Why could all possible scenarios (future and past) not be occuring simultaneously and simply cannot be detected by our current physics model?
And don’t say “They just can’t,” that’s a cop-out. 
–Tim
First question: We don’t know. Yes, Homer, that is a cop-out. Tough.
Second question: It would depend on the nature of the proof, and what, exactly, was proven. If I had any clue how to make such a proof, I’d do it.
I am not an expert on this but I believe there is a physics model that says every time a choice is made there are new universes created representing each option. I am not sure if this covers such decisions as what flavor of ice cream you will pick at Baskin Robbins (sp?). Maybe someone could enlighten us on that subject.
The Schrodinger’s Cat experiment was further theorized by a school of physics thought called the “Many Universes” theory. Recall from Schrodie’s cat that the cat wasn’t dead until it was witnessed and that the act of observing changed the outcome, i.e.; affected the “future”. The “Many Universes” theory went a step further and postulated that at the time the poison was released, there were two possible outcomes: cat lives, cat dies. These two outcomes existed simultaneously in two separate universes. That’s right, one with the cat alive and one with it dead. You, as the scientist, also existed in each universe, but were completely unaware of the other. When you looked in the box and saw the dead cat, it became impossible for the universe with you and the live cat to exist so it collapsed. I’ll have to dig up names of scientists/philosophers in this school.
Sprittle’s summary of the Many Worlds model is correct, but I hasten to point out that the Many Worlds model is not a scientific theory, as it is not falsifiable or verifiable. It properly belongs in the realm of philosophy.
I have to jump in here and correct a very common misconception about Schrodinger’s Cat, and quantum mechanics in general. If you have a quantum system (e.g. a decaying atom) in a superposition of states, the collapse is caused by forcing it into an interaction in which it can only be in one state or another. Any interaction which gathers significant information will do this. So it’s the way that we’re measuring it that causes the collapse, not the fact that a conscious human observer is noticing the information.
At least, that’s according to current quantum theory. (Which may be wrong for all we know, but seems to work.) As Chronos said, Many Worlds is pure philosophy, as I don’t see how we could ever know if it’s true or not.
Also, the cat is never in a superposition of states. It’s the atom that you hooked up to the detector which is in a superposition of states. The cat is just along for the ride.
On the other hand, relativity seems to imply that the future is “there” already, since it’s just another dimension of spacetime. Another way that relativity and QM have yet to be reconciled.
I have heard some claim that quantum computing infers that there are other universes, on the grounds that qubit computing is so massively parallel that it can produce results that theoretically exceed the classical computing capacity of all the particles in the observable universe!