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The Second Superstring Revolution
Some amazing and unexpected
equivalences called dualities have
been uncovered that imply:
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The five superstring theories
are actually five perturbative expansions
of a single underlying theory
about five different points! |
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Excitations of various dimensions, called p-branes,
occur in the non-perturbative spectrum. In certain respects they
are as fundamental as strings,
which in this context can be called one-branes. |
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A sixth limit of the theory
lives in eleven dimensions.
This vacuum solution does not have string excitations. Rather, it
has two-branes and five-branes. |
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