Effective Theory of Warped Compactifications and the Implications for KKLT

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.