Speaker
Description
Despite two decades of efforts, constructing metastable de Sitter vacua in String Theory continues to be a great challenge and the almost twenty-year-old construction of Kachru, Kallosh, Linde and Trivedi (KKLT), although not uncontested, remains the prototypical example. This proposal is a three-step construction that combines fluxes, non-perturbative phenomena and anti-D3 branes in a warped Calabi-Yau compactifaction with a deformed conifold-type throat. The first step, where the complex structure moduli are stabilized by fluxes that need to break supersymmetry in order to generate a very small Gukov-Vafa-Witten superpotential W0, has been criticized on both theoretical and practical counts. I will present a new, more minimalist de Sitter construction that does not require these additional supersymmetry-breaking (0,3) fluxes. This construction is based on the key observation that the addition of anti-D3 branes at the tip of a Klebanov-Strassler throat, which is necessary to uplift the cosmological constant, generates moreover three-form fluxes that precisely give rise to a non-trivial small superpotential as well as to F-terms for the dilaton and the conifold modulus parametrizing the size of the tip of the throat. I will describe these terms from both a first-principle ten-dimensional and a four-dimensional perspective, finding the same parametric dependence, and I will show that upon including Kahler-moduli stabilization, the resulting potential admits de Sitter minima with a small cosmological constant.
