RG-induced modulus stabilization: perturbative de Sitter vacua and improved D3-$$ \overline{\mathrm{D}3} $$ inflation

Abstract

We propose a new mechanism that adapts to string theory a perturbative method for stabilizing moduli without leaving the domain of perturbative control, thereby evading the ‘Dine-Seiberg’ problem. The only required nonperturbative information comes from the standard renormalization-group resummation of leading logarithms that allow us simultaneously to work to a fixed order in the perturbative parameter α and to all orders in α ln τ where τ is a large extra-dimensional modulus. The resulting potential is naturally minimized for moduli of order τ ~ e1/α and so can be exponentially large given $$ \mathcal{O} $$ O (10) input parameters. The mechanism relies on accidental low-energy scaling symmetries known to be generic and so is robust against UV details. The resulting compactifications generically break supersymmetry and 4D de Sitter solutions are relatively easy to achieve without additional uplifting. Variations on the theme lead to inflationary scenarios for which the size of the stabilized moduli differ significantly before and after inflation and so provide a dynamical mechanism whereby inflationary scales are much larger than late-time physical (e.g. supersymmetry breaking) scales, with this hierarchy contingent on past cosmic evolution with the inflaton playing a secondary late-time role as a relaxation field. We apply this formalism to warped D3-$$ \overline{\mathrm{D}3} $$ D 3 ¯ inflation using non-linearly realized supersymmetry to describe the antibrane tension and the Coulomb interaction, and show how doing so our perturbative modulus stabilization mechanism evades the η-problem that usually plagues this scenario. We speculate about the relevance of our formalism to tachyon condensation at later stages of brane-antibrane annihilation.

Loops, local corrections and warping in the LVS and other type IIB models

“…Independently, this represents a very general argument suggesting that the leading loop effect in the scalar potential scales as ∼ V −10/3 . This appears to clash with the existence of loop corrections ∼ V −8/3 which have recently been proposed in the literature [43].…”

“…In our analysis, we will have the Large Volume Scenario (LVS) [4,5] in the back of our minds as this is a prototypical example of a model with fluxes where a better understanding of loop and α corrections is crucial -see [32][33][34][35][36][37][38][39][40][41][42][43][44] for recent work on loop and α corrections in this and related settings. However, our findings are not restricted to the LVS and should be relevant more generally in the type-IIB context.…”

String Cosmology: from the Early Universe to Today

“…A detailed study of how moduli stabilisation can be incorporated in this set-up has been reviewed in [404] (crucial as including moduli stabilisation substantially changes the dynamics of the original proposal). See however a recent potential way-out exploiting perturbative stabilisation mechanism via RG effects [189] for which the warped inflation potential is at work even after moduli stabilisation.…”

Stringy multifield quintessence and the Swampland

“…Let us focus for simplicity on the simplest case with just one universal modulus τ b and one blow-up mode τ s with τ s τ b . This hierarchy can be achieved if at leading order τ b is stabilized exponentially large by balancing α against loop corrections as in [41,42]. The non-universal modulus τ s can then be fixed at subleading order by the interplay between higher order perturbative corrections as in [43].…”