Superpotential

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

The challenge of realizing F-term axion monodromy inflation in string theory

Abstract: A systematic analysis of possibilities for realizing single-field F-term axion monodromy inflation via the flux-induced superpotential in type IIB string theory is performed. In this well-defined setting the conditions arising from moduli stabilization are taken into account, where we focus on the complex-structure moduli but ignore the Kahler moduli sector. Our analysis leads to a no-go theorem, if the inflaton involves the universal axion. We furthermore construct an explicit example of F-term axion monodromy inflation, in which a single axion-like field is hierarchically lighter than all remaining complex-structure moduli.

Poly-instanton inflation

Abstract: We propose a new inflationary scenario in type IIB Calabi-Yau compactifications, where the inflaton is a Kahler modulus parameterising the volume of an internal four-cycle. The inflaton potential is generated via poly-instanton corrections to the superpotential which give rise to a naturally flat direction due to their double exponential suppression. Given that the volume mode is kept stable during inflation, all the inflaton-dependent higher dimensional operators are suppressed. Moreover, string loop effects can be shown to be negligible throughout all the inflationary dynamics for natural values of the underlying parameters. The model is characterised by a reheating temperature of the order Trh 106 GeV which requires Ne 54 e-foldings of inflation. All the inflationary observables are compatible with current observations since the spectral index is ns 0.96, while the tensor-to-scalar ratio is r 10−5. The volume of the Calabi-Yau is of order 103 in string units, corresponding to an inflationary scale around 1015 GeV.

An index for the Dirac operator on D3 branes with background fluxes

Abstract: We study the problem of instanton generated superpotentials in Calabi-Yau orientifold compactifications directly in type-IIB string theory. To this end, we derive the Dirac equation on a euclidean D3 brane in the presence of background fluxes. We propose an index which governs whether the generation of a superpotential in the effective 4d theory by D3 brane instantons is possible. Applying the formalism to various classes of examples, including the K3 x T-2/Z(2) orientifold, in the absence and presence of fluxes, we show that our results are consistent with conclusions attainable via duality from an M-theory analysis.

Non-Abelian Localization for Supersymmetric Yang-Mills-Chern-Simons Theories on Seifert Manifold

Abstract: We derive non-Abelian localization formulas for supersymmetric Yang-Mills-Chern-Simons theory with matters on a Seifert manifold $M$, which is the three-dimensional space of a circle bundle over a two-dimensional Riemann surface $\ensuremath{\Sigma}$, by using the cohomological approach introduced by K\"all\'en. We find that the partition function and the vacuum expectation value of the supersymmetric Wilson loop reduces to a finite dimensional integral and summation over classical flux configurations labeled by discrete integers. We also find that the partition function reduces further to just a discrete sum over integers in some cases, and evaluate the supersymmetric index (Witten index) exactly on ${S}^{1}\ifmmode\times\else\texttimes\fi{}\ensuremath{\Sigma}$. The index completely agrees with the previous prediction from field theory and branes. We discuss a vacuum structure of the Aharony-Bergman-Jafferis-Maldacena theory deduced from the localization.

N=1 Mirror Symmetry and Open/Closed String Duality

Abstract: We show that the exact N=1 superpotential of a class of 4d string compactifications is computed by the closed topological string compactified to two dimensions. A relation to the open topological string is used to define a special geometry for N=1 mirror symmetry. Flat coordinates, an N=1 mirror map for chiral multiplets and the exact instanton corrected superpotential are obtained from the periods of a system of differential equations. The result points to a new class of open/closed string dualities which map individual string world-sheets with boundary to ones without. It predicts an mathematically unexpected coincidence of the closed string Gromov-Witten invariants of one Calabi-Yau geometry with the open string invariants of the dual Calabi-Yau.