A new class of de Sitter vacua in type IIB large volume compactifications

Abstract

We construct a new class of metastable de Sitter vacua of flux compactifications of type IIB string theory. These solutions provide a natural extension of the 'Large Volume Scenario' anti-de Sitter vacua, and can analogously be realised at parametrically large volume and weak string coupling, using standard N = 1 supergravity. For these new vacua, a positive vacuum energy is achieved from the inclusion of a small amount of fluxinduced supersymmetry breaking in the complex structure and axio-dilaton sector, and no additional 'uplift' contribution (e.g. from anti-branes) is required. We show that the approximate no-scale structure of the effective theory strongly influences the spectrum of the stabilised moduli: one complex structure modulus remains significantly lighter than the supersymmetry breaking scale, and metastability requires only modest amounts of tuning. After discussing these general results, we provide a recipe for constructing de Sitter vacua on a given compactification manifold, and give an explicit example of a de Sitter vacuum for the compactification on the Calabi-Yau orientifold realised in CP 4 11169 . Finally, we note that these solutions have intriguing implications for phenomenology, predicting no superpartners in the spectrum below ∼50 TeV, and no WIMP dark matter.

De Sitter vs Quintessence in String Theory

“…The mechanisms proposed in the literature proceed instead in just a single step where a dS vacuum is achieved by the interplay of several contributions to the 4D scalar potential. Some of the most popular dS mechanisms are: ( i ) anti‐branes, () T‐branes, () effects, () non‐perturbative effects at singularities, ( v ) non‐zero S and U F‐terms 9.…”

“…In this case, after including the shift of the dilaton proportional to the blow‐up mode resolving the singularity, the corresponding non‐perturbative term generates a positive definite contribution to the scalar potential similar to that coming from anti‐branes. Concrete CY compactifications with these superpotentials have not been constructed yet and it would be an interesting avenue to explore. – Complex structure F‐terms : The complex structure moduli have minima at the supersymmetric points . However there may be further minima for these fields for which .…”

“…An intrinsic limitation of these constructions is the difficulty to realise explicit examples with large volume since they would require to fix a large number of complex structure moduli to achieve enough tuning freedom. A concrete example with was however constructed in [] but using a continuous flux approximation. – Non‐perturbative dS vacua : dS minima can emerge from stabilising all the geometric moduli in just one‐step via the inclusion of just background fluxes and non‐perturbative effects. The main problems of this approach are the poor knowledge of the S and U ‐moduli dependence of the prefactor of non‐perturbative effects and the computational difficulty to find a numerical solution for the minimisation equations in the presence of a large number of geometric moduli. – Heterotic dS vacua : The heterotic string compactified on smooth Calabi‐Yau threefolds can lead to 4D dS models where the gauge bundle moduli, together with the dilaton and the U ‐moduli are fixed supersymmetrically at leading order via the requirement of a holomorphic gauge bundle, fractional fluxes and non‐perturbative effects.…”

Gaugino condensation and small uplifts in KKLT

“…3 For further dS proposals involving balancing classical and quantum effects, see e.g. [58,59,52,[60][61][62][63][64][65][66][67][68][69][70]32], and the recent review [71]. For a new perspective on dark energy from F-theory, see [72,73].…”

Hidden sectors in string theory: kinetic mixings, fifth forces and quintessence

“…In this context, the simplest possibility is to stabilise all the moduli at a de Sitter minimum. The most well-developed models for such a scenario are in type IIB [16][17][18][19][20][21][22][23][24][25][26][27], where fluxes threading the internal cycles are responsible for a large multitude of solutions [28][29][30][31][32]. Models in M-theory were constructed in [33].…”