D =7/D =6 heterotic supergravity with gauged R-symmetry

Abstract

We construct a family of chiral anomaly-free supergravity theories in D = 6 starting from D = 7 supergravity with a gauged noncompact R-symmetry, employing a Hořava-Witten bulk-plus-boundary construction. The gauged noncompact R-symmetry yields a positive (de Sitter sign) D = 6 scalar field potential. Classical anomaly inflow which is needed to cancel boundary-field loop anomalies requires careful consideration of the gravitational, gauge, mixed and local supersymmetry anomalies. Coupling of boundary hypermultiplets requires care with the Sp(1) gauge connection required to obtain quaternionic Kähler target manifolds in D = 6. This class of gauged R-symmetry models may be of use as starting points for further compactifications to D = 4 that take advantage of the positive scalar potential, such as those proposed in the scenario of supersymmetry in large extra dimensions. *

Self-tuning at large (distances): 4D description of runaway dilaton capture

“…This could happen at the string scale if the brane UV completes as an object within string theory, or it could happen above or below the scale M if the branes UV complete as vortices in a higher-dimensional field theory. For concreteness we consider the vortex completion, since the extension to string theory of the system used here remains an open question [54][55][56][57]. Since our goal is to explore extra-dimensional approaches to the hierarchy problem, we always take the brane SUSY-breaking scale, M s , much larger than electroweak scales: M s m. If we choose M s M then the vortex sector would be supersymmetric (in that it would preserve at most half of the supersymmetries of the bulk [62][63][64]) with the branes likely arising as BPS solutions.…”

Braneworld localisation in hyperbolic spacetime

“…One way to view this would be as a 7D to 6D reduction starting from the 7D theory on H (2,2) [13], thus obtaining a 6D chiral (1, 0) 10 The specific form (5.25) of the ξ0 zero-mode has the agreeable property that the coefficients of yet higher-order terms in hµν (x) in the 4D effective action can also be explicitly evaluated. One finds Ip ≡ supersymmetric theory with potential anomalies arising from anomaly inflow, and hence requiring compensating 6D matter fields [22]. Another way to view it would be as a 5D to 4D reduction after the additional S 2 & monopole reduction from 7D, thus producing a 4D chiral N=1 supersymmetric theory, again with anomaly inflow requiring compensating 4D matter fields [21].…”

“…Another worldvolume coordinate, y, may be chosen to be compactified on S 1 , or can be used in an S 1 /Z 2 Hořava-Witten [20] type construction in order to produce a 4D chiral theory, with attendant matter fields as needed to cancel anomaly inflow [21,22]. The 4D effective gravity is next analysed.…”

Invariants and divergences in half-maximal supergravity theories

“…Such entanglements of gauge and supersymmetry anomalies are familiar from the anomaly analysis of Hořava-Witten type brane constructions[84].…”