Warped compactifications in supergravity: A p-brane model

Abstract

In 4D particle phenomenology beyond the Standard Model, warped compactification of higher dimensional gravity provides a geometric mechanism for generating large hierarchies of 4D physical scales. However, realizing such backgrounds in supergravity is constrained by the Maldacena–Nu˜nez no-go theorem. Under its assumptions, two-derivative supergravity with positive-energy ingredients obstructs nontrivially warped compactifications to de Sitter or Minkowski space. In string theory, we can evade such a restriction by adding negative tension sources, such as orientifold planes, to the theory. We study the role of negative tension sources for a p-brane model, which can be generalised to a type II supergravity. We explicitly construct the localized source action for this model using Dirac–Born–Infeld and Wess–Zumino terms and match it to the p-brane background with compact internal space. We find that the compactness of the internal space requires an effective negative-tension source. Hence, we get an analogous realization of the mechanism by which orientifold-like negative-tension sources allow warped backgrounds in string theory.