Irina Arefeva (Moscow):

D-brane decay and cosmological dark energy

Abstract:

A possibility for the Universe to cross the w=-1 cosmological constant barrier for the dark energy state parameter is explored. The Universe is considered as a slowly decaying D3-brane. The D3-brane dynamics is approximately described by a nonlocal string tachyon interaction and a back reaction of gravity is incorporated in the closed string tachyon dynamics. In a local approximation this model contains one effective phantom component and oneusual field with a simple polynomial interaction. We find restrictions on this interaction under which it is possible to reach w=-1 from below at large time. We study a stability of this solution under under incorporation cold dark matter.

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