/ 03 07 07 1 v 3 1 O ct 2 00 3 Where new gravitational physics comes from : M - theory ?
نویسنده
چکیده
It is suggested [1] that current cosmic acceleration arises due to modification of General Relativity by the terms with negative powers of curvature. We argue that time-dependent (hyperbolic) compactifications of 4 + n-dimensional gravity ( string/M-theory) lead to the effective 4d gravity which naturally contains such terms. The same may be achieved in the braneworld by the proper choice of the boundary action. Hence, such a model which seems to eliminate the need for dark energy may have the origin in M-theory. PACS numbers: 98.80.-k,04.50.+h,11.10.Kk,11.10.Wx Electronic mail: [email protected], [email protected] Electronic mail: [email protected] Also at TSPU, Tomsk, Russia
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