A Study of Accelerating Cosmologies from Superstring/M Theories
نویسنده
چکیده
We study aspects of the accelerating cosmologies obtained from the compactification of vacuum solution and S2-branes of superstring/M theories. Parameter dependence of the resulting expansion of our universe and internal space is examined for all cases. We find that accelerated expansions are obtained also from spherical internal spaces, albeit the solution enters into contracting phase eventually. The relation between the models of SM2and SD2-branes are also discussed, and a potential problem with SD2-brane model is noted. ∗e-mail address: [email protected]
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