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In this article, we point out that to solve the null Raychaudhuri equation for higher dimensional spacetime with accelerating FRW solution in external directions and static compact internal directions, it is necessary to violate the Strong Energy condition in higher dimensions. This constraint is well-known in obtaining accelerating cosmological solutions in string compactification, first described by Gibbons-Maldacena-Nunez. In deriving this constraint, we do not make any assumptions regarding the matter content.

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