Cosmological String Solutions by Dimensional Reduction †
نویسنده
چکیده
We obtain cosmological four-dimensional solutions of the low-energy effective string theory by reducing a five-dimensional black hole, and black hole–de Sitter solution of the Einstein gravity down to four dimensions. The appearance of a cosmological constant in the five dimensional Einstein–Hilbert action produces a special dilaton potential in the four-dimensional effective string action. Cosmological scenarios implemented by our solutions are discussed. †Work supported by the Department of Energy, contract DE–AC03–76SF00515. ‡e-mail: [email protected], Work supported by a grant of the DAAD ∗∗e-mail: [email protected], Work supported by a grant of MINERVA
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