Where does matter come from? Here's the quick answer:
There's "positive energy" and "negative energy". "Positive Energy" is what we call "energy" and matter. The "Negative Energy" is most likely gravity. If one would add up all of the "Positive Energy" and "Negative Energy", and add them, it would add up to zero.
You can't create energy, from what we know now, but you can borrow. Everytime you borrow, there's just as much negative energy created for all of the positive energy that was made.
That's quick and dirty so if you want more, I can give you more, but I think there are those who may already be able to point out to you some link.
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When all else fails, check the manual