Superpotential

About: Superpotential is a research topic. Over the lifetime, 3836 publications have been published within this topic receiving 137867 citations.

On D3-brane Potentials in Compactifications with Fluxes and Wrapped D-branes

Abstract: We study the potential governing D3-brane motion in a warped throat region of a string compactification with internal fluxes and wrapped D-branes. If the Kahler moduli of the compact space are stabilized by nonperturbative effects, a D3-brane experiences a force due to its interaction with D-branes wrapping certain four-cycles. We compute this interaction, as a correction to the warped four-cycle volume, using explicit throat backgrounds in supergravity. This amounts to a closed-string channel computation of the loop corrections to the nonperturbative superpotential that stabilizes the volume. We demonstrate that for warped conical spaces the superpotential correction is given by the embedding equation specifying the wrapped four-cycle, in agreement with the general form proposed by Ganor. We verify that the corrected gauge coupling on wrapped D7-branes is holomorphic. Finally, our results have applications to cosmological inflation models in which the inflaton corresponds to a D3-brane moving in a warped throat.

Supersymmetric three-form flux perturbations on AdS 5

Abstract: We consider warped type IIB supergravity solutions with three-form flux and $\mathcal{N}=1$ supersymmetry, which arise as the supergravity duals of confining gauge theories We first work in a perturbation expansion around ${\mathrm{AdS}}_{5}\ifmmode\times\else\texttimes\fi{}{\mathrm{S}}^{5}$, as in the work of Polchinski and Strassler, and from the $\mathcal{N}=1$ conditions and the Bianchi identities recover their first-order solution generalized to an arbitrary $\mathcal{N}=1$ superpotential We find the second order dilaton and axion by the same means We also find a simple family of exact solutions, which can be obtained from solutions found by Becker and Becker, and which includes the recent Klebanov-Strassler solution

Kahler moduli inflation

Abstract: We show that under general conditions there is at least one natural inflationary direction for the Kahler moduli of type-IIB flux compactifications. This requires a Calabi-Yau which has h^{1,1}>2$>h2,1>h1,1>2 and for which the structure of the scalar potential is as in the recently found exponentially large volume compactifications. We also need - although these conditions may be relaxed - at least one Kahler modulus whose only non-vanishing triple-intersection is with itself and which appears by itself in the non-perturbative superpotential. Slow-roll inflation then occurs without a fine tuning of parameters, evading the η problem of F-term inflation. In order to obtain COBE-normalised density perturbations, the stabilised volume of the Calabi-Yau must be (105−107) in string units, and the inflationary scale Minfl ~ 1013 GeV. We find a robust model independent prediction for the spectral index of 1−2/Ne = 0.960→0.967, depending on the number of efoldings.

d-Brane Instantons in Type II Orientifolds

Abstract: We review recent progress in determining the effects of d-brane instantons in supersymmetric compactifications of Type II string theory to four dimensions. We describe the abstract d-brane instanton calculus for holomorphic couplings such as the superpotential, the gauge kinetic function, and higher fermionic F-terms, and we briefly discuss the implications of background fluxes for the instanton sector. We then summarize the concrete consequences of stringy d-brane instantons for the construction of semirealistic models of particle physics or supersymmetry breaking in compact and noncompact geometries.