Out of this world supersymmetry breaking

We show that in a general hidden sector model, supersymmetry breaking neces sarily generates at one loop a scalar and gaugino mass as a consequence of the super-Weyl anomaly. We study a scenario in which this contribution domi nates. We consider the Standard Model particles to be localized on a (3 + 1 )-dimensional subspace or "3-brane" of a higher dimensional spacetime, whil e supersymmetry breaking occurs off the 3-brane, either in the bulk or on a nother 3-brane. At least one extra dimension is assumed to be compactified roughly one to two orders of magnitude below the four-dimensional Planck sc ale. This framework is phenomenologically very attractive; it introduces ne w possibilities for solving the supersymmetric flavor problem, the gaugino mass problem, the supersymmetric CP problem, and the mu-problem. Furthermor e, the compactification scale can be consistent with a unification of gauge and gravitational couplings. We demonstrate these claims in a four-dimensi onal effective theory below the compactification scale that incorporates th e relevant features of the underlying higher dimensional theory and the con tribution of the super-Weyl anomaly. Naturalness constraints follow not onl y from symmetries but also from the higher dimensional origins of the theor y. We also introduce additional bulk contributions to the MSSM soft masses. This scenario is very predictive: the gaugino masses, squark masses, and A terms are given in terms of MSSM renormalization group functions. (C) 1999 Published by Elsevier Science B.V. All rights reserved.