Hi uranium_235,
Edward Witten of the Institute for Advanced Study in Princeton is the man behind the M-Theory. He came up with a unified formula that explained the 5 superstring theories we have in 10 dimensions by adding another dimension. He named it M-theory (never explained what the M stands for though, perhaps Membranes).
Check out this link by Dr. Michio Kaku:
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I don't know too much about the theory, but I won't argue with the brightest minds of today who are working on it.
Here's a quote from the article:
"Since string theory is really a theory of Creation, when all its beautiful symmetries were in their full glory, the only way to test it, the critics wail, is to re-create the Big Bang itself, which is impossible"
In other words,
really interesting