The Cosmological Constant and Warped Extra Dimensions
نویسنده
چکیده
Abstract We study the behavior of a general gravitational action, including quadratic terms in the curvature, supplemented by a compact scalar field in 4 + 1 dimensions. The generalized Einstein equation for this system admits solutions which are compact in one direction and Poincaré invariant in the remaining directions. These solutions do not require any fine-tuning of the parameters in the action—including the cosmological constant—only that they should satisfy some mild inequalities. Some of these inequalities can be expressed in a universal form that does not depend on the number of extra compact dimensions when the scenario is generalized beyond 4 + 1 dimensions.
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