Non-simply Laced Groups Research Articles

N = 3 SCFTs in 4 dimensions and non-simply laced groups

In this paper we discuss various N = 3 SCFTs in 4 dimensions and in particular those which can be obtained as a discrete gauging of an N = 4 SYM theories with non- simply laced groups. The main goal of the project was to compute the Coulomb branch superconformal index and moduli space Hilbert series for the N = 3 SCFTs that are obtained from gauging a discrete subgroup of the global symmetry group of N = 4 Super Yang-Mills theory. The discrete subgroup contains elements of both SU(4) R-symmetry group and the S-duality group of N = 4 SYM. This computation was done for the simply laced groups (where the S-duality groups is SL(2, ℤ) and Langlands dual of the algebra {}^Lmathfrak{g} is simply mathfrak{g} ) by Bourton et al. [1], and we extended it to the non-simply laced groups. We also considered the orbifolding groups of the Coulomb branch for the cases when Coulomb branch is relatively simple; in particular, we compared them with the results of Argyres et al. [2], who classified all N≥ 3 moduli space orbifold geometries at rank 2 and with the results of Bonetti et al. [3], who listed all possible orbifolding groups for the freely generated Coulomb branches of N≥ 3 SCFTs. Finally, we have considered sporadic complex crystallographic reflection groups with rank greater than 2 and analyzed, which of them can correspond to an N = 3 SCFT with a principal Dirac pairing.

Enhanced gauge symmetry in type II and F-theory compactifications: Dynkin diagrams from polyhedra

We explain the observation by Candelas and Font that the Dynkin diagrams of non-abelian gauge groups occurring in type IIA and F-theory can be read off from the polyhedron Δ ∗ that provides the toric description of the Calabi-Yau manifold used for compactification. We show how the intersection pattern of toric divisors corresponding to the degeneration of elliptic fibers follows the ADE classification of singularities and the Kodaira classification of degenerations. We treat in detail the cases of elliptic K3 surfaces and K3 fibered threefolds where the fiber is again elliptic. We also explain how even the occurrence of monodromy and non-simply laced groups in the latter case is visible in the toric picture. These methods also work in the fourfold case.

LEVEL-ONE SU(N) WZNW MODELS ON HIGHER-GENUS RIEMANN SURFACES

Using factorization properties and fusion rules, we find the higher-genus partition function and two-point correlators for the SU (N)1 WZNW model. The result has simple form in terms of higher-genus theta functions on the group manifold. The previously known results of SU (2)1 and SU (3)1 are also obtained as special cases. This method, combined with other considerations such as modular invariance, can be extended to the nonsimply laced groups and higher-level WZNW models.

Torus compactification for non-simply laced groups

Non-simply laced gauge groups are obtained from torus compactification of the interacting 26-dimensional bosonic string.