Magnetized E3-brane instantons in F-theory

151

443

We introduce a class of four dimensional field theories constructed by quotienting ordinary N = 4 U(N ) SYM by particular combinations of R-symmetry and SL(2, Z) automorphisms. These theories appear naturally on the worldvolume of D3 branes probing terminal singularities in F-theory, where they can be thought of as non-perturbative generalizations of the O3 plane. We focus on cases preserving only 12 supercharges, where the quotient gives rise to theories with coupling fixed at a value of order one. These constructions possess an unconventional large N limit described by a non-trivial F-theory fibration with base AdS 5 × (S 5 /Z k ). Upon reduction on a circle the N = 3 theories flow to well-known N = 6 ABJM theories.

Section: Preserved Superchargesmentioning

confidence: 99%

N = 3 $$ \mathcal{N}=3 $$ four dimensional field theories

García-Etxebarria

Regalado

2016

151

443

“…Thus, the SO(8) gauge group is unbroken. By switching on a proper rigidifying flux, we could lift the deformation moduli [26,50,51]. Hence, for the B-field (3.24), we have a pure super Yang-Mills theory in the hidden sector which undergoes gaugino condensation.…”

Section: Jhep05(2014)001mentioning

confidence: 99%

Explicit de Sitter flux vacua for global string models with chiral matter

Cicoli

Klevers

Krippendorf³

et al. 2014

137

222

Abstract:We address the open question of performing an explicit stabilisation of all closed string moduli (including dilaton, complex structure and Kähler moduli) in fluxed type IIB Calabi-Yau compactifications with chiral matter. Using toric geometry we construct Calabi-Yau manifolds with del Pezzo singularities. D-branes located at such singularities can support the Standard Model gauge group and matter content or some close extensions. In order to control complex structure moduli stabilisation we consider CalabiYau manifolds which exhibit a discrete symmetry that reduces the effective number of complex structure moduli. We calculate the corresponding periods in the symplectic basis of invariant three-cycles and find explicit flux vacua for concrete examples. We compute the values of the flux superpotential and the string coupling at these vacua. Starting from these explicit complex structure solutions, we obtain AdS and dS minima where the Kähler moduli are stabilised by a mixture of D-terms, non-perturbative and perturbative α ′ corrections as in the LARGE Volume Scenario. In the considered example the visible sector lives at a dP 6 singularity which can be higgsed to the phenomenologically interesting class of models at the dP 3 singularity.

“…ED3 wrapping a K3 fibre: In this case we need h 2,0 + (K3) = 1 and h 2,0 − (K3) = 0, implying that the ED3 is on top of the O7 − -plane giving an Sp(2) instead of an O(1) instanton which does not contribute to the superpotential. However the ED3 might contribute to W if we magnetise the instanton since the fluxes (both background and word-volume fluxes) may play a crucial rôle to lift the universal zero-modes of an Sp(2) instanton giving rise to a contribution to the superpotential [48,49]. A more exotic option would be to consider an O7 + instead of an O7 − -plane in which case an ED3 sitting on top of the O7 + -plane would correctly yield an O(1) instanton.…”

Section: Jhep10(2011)119mentioning

confidence: 99%

Anisotropic modulus stabilisation: strings at LHC scales with micron-sized extra dimensions

Cicoli

Burgess

Quevedo

2011

151

We construct flux-stabilised Type IIB string compactifications whose extra dimensions have very different sizes, and use these to describe several types of vacua with a TeV string scale. Because we can access regimes where two dimensions are hierarchically larger than the other four, we find examples where two dimensions are micron-sized while the other four are at the weak scale in addition to more standard examples with all six extra dimensions equally large. Besides providing ultraviolet completeness, the phenomenology of these models is richer than vanilla large-dimensional models in several generic ways: (i) they are supersymmetric, with supersymmetry broken at sub-eV scales in the bulk but only nonlinearly realised in the Standard Model sector, leading to no MSSM superpartners for ordinary particles and many more bulk missing-energy channels, as in supersymmetric large extra dimensions (SLED); (ii) small cycles in the more complicated extra-dimensional geometry allow some KK states to reside at TeV scales even if all six extra dimensions are nominally much larger; (iii) a rich spectrum of string and KK states at TeV scales; and (iv) an equally rich spectrum of very light moduli exist having unusually small (but technically natural) masses, with potentially interesting implications for cosmology and astrophysics that nonetheless evade new-force constraints. The hierarchy problem is solved in these models because the extra-dimensional volume is naturally stabilised at exponentially large values: the extra dimensions are Calabi-Yau geometries with a 4D K3 or T 4 -fibration over a Open Access doi:10.1007/JHEP10 (2011)119 JHEP10 (2011)119 2D base, with moduli stabilised within the well-established LARGE-Volume scenario. The new technical step is the use of poly-instanton corrections to the superpotential (which, unlike for simpler models, are likely to be present on K3 or T 4 -fibered Calabi-Yau compactifications) to obtain a large hierarchy between the sizes of different dimensions. For several scenarios we identify the low-energy spectrum and briefly discuss some of their astrophysical, cosmological and phenomenological implications.