Waldemar Schulgin

Moduli Stabilization in Type IIB Orientifolds (II)

We discuss general properties of moduli stablization in KKLT scenarios in type IIB orientifold compactifications X6. In particular, we find conditions for the Kähler potential to allow a KKLT scenario for a manifold X6 without complex structure moduli, i.e. h(2,1)(X6) = 0. This way, a whole class of type IIB orientifolds with h(2,1)(X6) = 0 is ruled out. This excludes in particular all ZN–and ZN ×ZM–orientifolds X6 with h(2,1)(X6) = 0 for a KKLT scenario. This concerns Z3,Z7,Z3×Z3,Z4×Z4,Z6×Z6 and Z2×Z6′ –both at the orbifold point and away from it. Furthermore, we propose a mechanism to stabilize the Kaehler moduli accociated to the odd cohomology H (1,1) − (X6). In the second part of this work we discuss the moduli stabilization of resolved type IIB ZN– or ZN ×ZM–orbifold/orientifold compactifications. As examples for the resolved Z6 and Z2 × Z4 orbifolds we fix all moduli through a combination of fluxes and racetrack superpotential.

Two loop integrability for Chern-Simons theories with = 6 supersymmetry

We consider two-loop anomalous dimensions for fermionic operators in the ABJM model and the ABJ model. We find the appropriate Hamiltonian and show that it is consistent with a previously predicted Bethe ansatz for the ABJM model. The difference between the ABJ and ABJM models is invisible at the two-loop level due to cancelation of parity violating diagrams. We then construct a Hamiltonian for the full two-loop OSp(6|4) spin chain by first constructing the Hamiltonian for an SL(2|1) subgroup, and then lifting to OSp(6|4). We show that this Hamiltonian is consistent with the Hamiltonian found for the fermionic operators.

Moduli stabilization in type IIB orientifolds (I): Orbifold limits

Abstract We discuss general properties of moduli stabilization in KKLT scenarios in type IIB orientifold compactifications X 6 . In particular, we find conditions for the Kahler potential to allow a KKLT scenario for a manifold X 6 without complex structure moduli, i.e. h ( 2 , 1 ) ( − ) ( X 6 ) = 0 . This way, a whole class of type IIB orientifolds with h ( 2 , 1 ) ( − ) ( X 6 ) = 0 is ruled out. This excludes in particular all Z N - and Z N × Z M -orientifolds X 6 with h ( 2 , 1 ) ( X 6 ) = 0 for a KKLT scenario. This concerns Z 3 , Z 7 , Z 3 × Z 3 , Z 4 × Z 4 , Z 6 × Z 6 and Z 2 × Z 6 ′ -both at the orbifold point and away from it. Furthermore, we propose a mechanism to stabilize the Kahler moduli associated to the odd cohomology H − ( 1 , 1 ) ( X 6 ) . In the second part of this work we discuss the moduli stabilization of resolved type IIB Z N - or Z N × Z M -orbifold/orientifold compactifications. As examples for the resolved Z 6 and Z 2 × Z 4 orbifolds we fix all moduli through a combination of fluxes and racetrack superpotential.

Fermion Zero Modes in the Presence of Fluxes and a Non-perturbative Superpotential

We study the effect of background fluxes of general Hodge type on the supersymmetry conditions and on the fermionic zero modes on the world-volume of a Euclidean M5/D3-brane in M-theory/type IIB string theory. Using the naive susy variation of the modulino fields to determine the number of zero modes in the presence of a flux of general Hodge type, an inconsistency appears. This inconsistency is resolved by a modification of the supersymmetry variation of the modulinos, which captures the back-reaction of the non-perturbative effects on the background flux and the geometry.

Correlation Functions and Hidden Conformal Symmetry of Kerr Black Holes

Extremal scalar three-point correlators in the near-NHEK geometry of Kerr black holes have recently been shown to agree with the result expected from a holographically dual non-chiral two-dimensional conformal field theory. In this paper we extend this calculation to extremal three-point functions of scalars in a general Kerr black hole which need not obey the extremality condition

Massive tensor multiplets in N = 1 supersymmetry†

M = \sqrt {J}

Extremal three-point correlators in Kerr/CFT

. It was recently argued that for low frequency scalars in the Kerr geometry there is a dual conformal field theory description which determines the interactions in this regime. Our results support this conjecture. Furthermore, we formulate a recipe for calculating finite-temperature retarded three-point correlation functions which is applicable to a large class of (even non-extremal) correlators, and discuss the vanishing of the extremal couplings.

Nongeometric fluxes as supergravity backgrounds

We derive the action for a massive tensor multiplet coupled to chiral and vector multiplets as it can appear in orientifold compactifications of type IIB string theory. We compute the potential of the theory and show its consistency with the corresponding Kaluza-Klein reduction of N = 1 orientifold compactifications. The potential contains an explicit mass term for the scalar in the tensor multiplet which does not arise from eliminating an auxiliary field. A dual action with an additional massive vector multiplet is derived at the level of superfields.

Liouville theory beyond the cosmological horizon

We compute three-point correlation functions in the near-extremal, near-horizon region of a Kerr black hole, and compare to the corresponding finite-temperature conformal field theory correlators. For simplicity, we focus on scalar fields dual to operators