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arXiv · hep-th/9909103

Constraints on a Brane-World from the Vanishing of the Cosmological Constant

U. Ellwanger
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Abstract

We derive the analogue of the vanishing of the cosmological constant in 3+1 dimensions, T_0^0 = 0, in terms of an integral over components of the energy-momentum tensor of a 4+1 dimensional universe with parallel three-branes, and an additional constraint local to the branes. The basic ingredients are the existence of a static solution of the Einstein equations, and the compactness of the 5th dimension. The corresponding constraints are applied to a general action of scalar fields with arbitrary potentials in the bulk and on the branes. The equations of motion are solved in a linearized approximation in the 5th dimension, whereupon they require the search for extrema of an ``effective potential'', which depends nonlinearly on the action in the bulk and on the branes. The previous constraints then turn into the vanishing of this ``effective potential'' at the extremum.

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U. Ellwanger. 1999-09-24. Constraints on a Brane-World from the Vanishing of the Cosmological Constant. https://doi.org/10.1016/s0370-2693(99)01511-7

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