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Abstract We consider the conundrum of generating de Sitter space from higher‐dimensional geometry, with particular attention to KKLT‐type constructions[3] and their 5d implications. We show that even in the probe approximation with small, a consistent higher‐dimensional solution requires a deformation of a modulus field playing the role of a Goldberger‐Wise stabilizing field in Randall‐Sundrum type geometries that occurs through a shift in a the throat length. We identify the light radion field that sets the length of the throat, whose origin is the dynamical conifold deformation parameter. By analyzing the theory as a 5d model of mismatched branes in AdS5 space with a GW stabilization mechanism, we show how energy (and supersymmetry breaking) is transferred to both the IR and UV regions of the throat to generate a consistent 4d de Sitter sliced geometry. This should help resolve some of the recent apparent paradoxes in explicit higher‐dimensional constructions. Moreover, the radion gives insight into the potential for the previously identified “conifold instability”. We argue that this instability would be a destabilization of the potential for the radion in KKLT, which can occur when the perturbation is too large. If indeedis too small, the radion would enter on its runaway direction and the conifold deformation would shrink to zero size. It is difficult to satisfy the required bound and a) maintain a hierarchy in the simpler CY manifolds and b) complete the cosmological phase transition into the stabilized throat, We also discuss the implications of this type of setup for supersymmetry breaking, and how multiple throats can introduce hierarchies of supersymmetry breaking masses, even in an anomaly‐mediated scenario. In an appendix we consider general compactification constraints.
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Effective Theory of Warped Compactifications and the Implications for KKLT
Abstract We argue that effective actions for warped compactifications can be subtle, with large deviations in the effective potential from naive expectations owing to constraint equations from the higher‐dimensional metric. We demonstrate this deviation in a careful computation of the effective potential for the conifold deformation parameter of the Klebanov‐Strassler solution. The uncorrected naive effective potential for the conifold was previously used to argue that the Klebanov‐Strassler background would be destabilized by antibranes placed at the conifold infrared tip unless the flux was uncomfortably large. We show this result is too strong because the formerly neglected constraint equations eliminate the features of the potential that allowed for the instability in the de Sitter uplift of the KKLT scenario.
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- Award ID(s):
- 1915071
- PAR ID:
- 10444637
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Fortschritte der Physik
- Volume:
- 70
- Issue:
- 7-8
- ISSN:
- 0015-8208
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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