Related papers: Formation of Non-Abelian Monopoles Connected by St…
I review some aspects of BPS magnetic monopoles and of electric-magnetic duality in theories with arbitrary gauge groups. When the symmetry is maximally broken to a U(1)^r subgroup, all magnetically charged configurations can be understood…
I study the spontaneous breakdown of supersymmetry when higher-dimensional Yang-Mills or the type-I $SO(32)$ string theory are compactified on magnetized tori. Because of the universal gyromagnetic ratio $g=2$, the splittings of all…
We investigate all spherically symmetric fundamental monopole solutions with fixed topological charge in the SU(5) --> SU(3)xSU(2)xU(1)/Z_3xZ_2 symmetry breaking. We find that there is three-fold replication of the monopoles. The three…
Starting from the bosonic part of N=2 Super QCD with a 'Seiberg-Witten' N=2 breaking mass term, we obtain string BPS conditions for arbitrary semi-simple gauge groups. We show that the vacuum structure is compatible with a symmetry breaking…
The aim of superstring phenomenology is to develop the tools and methodology needed to confront string theory with experimental data. The first mandatory task is to find string solutions which reproduce the observable data. The subsequent…
The lepton sector masses and mixing angles can be explained in models based on $A_4$ symmetry. $A_4$ is a non-Abelian discrete group. Therefore, one issue in constructing models based on it is explaining the origin of $A_4$. A plausible…
We study {2Q+1}-strings connecting two static charges Q in (2+1)-d SU(2) Yang-Mills theory. While the fundamental {2}-string between two charges Q = 1/2 is unbreakable, the adjoint {3}-string connecting two charges Q = 1 can break. When a…
Attempts to construct chromodyons - objects with both magnetic charge and non-Abelian electric charge - in the context of spontaneously broken gauge theories have been thwarted in the past by topological obstructions to globally defining…
Topological defects can naturally be formed soon after bubble nucleation in the open inflation scenario. The defects are not completely diluted away by the subsequent period of inflation in the bubble interior and can produce observable…
Various dynamical regimes associated with confined monopoles in the Higgs phase of N=2 two-flavor QCD are studied. The microscopic model we deal with has the SU(2)xU(1) gauge group, with a Fayet-Iliopoulos term of the U(1) factor, and large…
We define and study certain hyperkaehler manifolds which capture the asymptotic behaviour of the SU(2)-monopole metric in regions where monopoles break down into monopoles of lower charges. The rate at which these new metrics approximate…
We study the breaking of the string spanned between test charges in the three dimensional Abelian Higgs model with compact gauge field and fundamentally charged Higgs field at zero temperature. In agreement with current expectations we…
We study four dimensional $N=2$ supersymmetric gauge theories with matter multiplets. For all such models for which the gauge group is $SU(2)$, we derive the exact metric on the moduli space of quantum vacua and the exact spectrum of the…
By using zero-norm states in the spectrum, we explicitly demonstrate the existence of an infinite number of high energy symmetry structures of the closed bosonic string theory. Each symmetry transformation (except those generated by…
A consistent theory of supersymmetry breaking must have a hidden sector, an observable sector, and must be embedded in a locally supersymmetric theory which arises from string theory. For phenomenological reasons it must also transmit…
A careful treatment of closed string BRST cohomology shows that there are more discrete states and associated symmetries in $D=2$ string theory than has been recognized hitherto. The full structure, at the $SU(2)$ radius, has a natural…
In the context of the gauge-string correspondence, we discuss the spontaneous partial breaking of supersymmetry. Starting from the orbifold of S^5, supersymmetry breaking leads us to consider the (resolved) conifold background and some of…
We claim that 3d monopole quivers, theories with product gauge groups interacting through Affleck-Harvey-Witten superpotentials, are a natural setup for the study of spontaneous breaking 3d $\mathcal{N}=2$ supersymmetry. We give evidence of…
We study a class of four-dimensional N=1 heterotic string theories which have nontrivial quantum dynamics arising from asymptotically free gauge groups. These models are obtained by orbifolding 4d N=2 heterotic/type II dual pairs by…
We explain a new construction of self-dual string solutions to the non-abelian two-form self-duality equation proposed in \cite{CK}. This class of self-dual strings is determined by the BPS monopoles in four-dimensions and the self dual…