Related papers: Surface Defects from Fractional Branes -- I
Extending our previous work on SU(3), we construct spherically symmetric BPS saturated regular configurations of N=4 SU(N) supersymmetric Yang-Mills theory preserving 1/4 supersymmetry, and investigate their features. We also give exact…
We study theories with sixteen supercharges and a discrete energy spectrum. One class of theories has symmetry group $SU(2|4)$. They arise as truncations of ${\cal N}=4$ super Yang Mills. They include the plane wave matrix model, 2+1 super…
We study a ${{\IZ}}_2$ orbifold of Type 0B string theory by reflection of six of the coordinates (this theory may also be thought of as a ${{\IZ}}_4$ orbifold of Type IIB string theory by a rotation by $\pi$ in three independent planes). We…
Topological duality defects arise as codimension one generalized symmetry operators in quantum field theories (QFTs) with a duality symmetry. Recent investigations have shown that in the case of 4D $\mathcal{N} = 4$ Super Yang-Mills (SYM)…
There are many conceivable possibilities of embedding the MSSM in string theory. These proceedings describe an approach which is based on grand unification in higher dimensions. This allows one to obtain global string-derived models with…
Three-dimensional Yang-Mills theory allows for a deformation quadratic in the field strengths which can not be integrated to a local action without auxiliary fields. Yet, its covariant divergence consistently vanishes after iterating the…
In $SU(N)$ Yang-Mills theory without matter, there exist stable long electric fluxtube strings which carry a 1-form symmetry charge. Over the past decade or so, there has been increasing evidence from lattice calculations that the…
This thesis is devoted to the study of a class of constructions based on Superstring Theory, baptized in the literature as Intersecting Brane Worlds. In particular we explore several issues regarding the proposal of Intersecting Brane…
We briefly review a class of four dimensional $\mathcal N=3$ field theories constructed by taking a quotient of $\mathcal N=4$ SYM with gauge group $U(N)$. The quotient involves a discrete symmetry that only exists for specific, order one,…
The possibility of radiative gauge symmetry breaking on D3-branes at non-supersymmetric orbifold singularities is examined. As an example, a simple model of D3-branes at non-supersymmetric C^3/Z_6 singularity with some D7-branes for the…
We describe the structure of string vacuum states in the supersymmetric matrix model for M theory compactified on a circle in the large-N limit. We show that the theory admits topological instanton field configurations which at…
We study the anomalies of two-dimensional BPS defects in six-dimensional $\mathcal{N}=(1,0)$ superconformal field theories. Using a holographic description of these defects furnished by probe D4-branes in AdS${}_7$ solutions of…
We carry out a gauge invariant analysis of certain perturbations of $D-2$-branes solutions of low energy string theories. We get generically a system of second order coupled differential equations, and show that only in very particular…
This is a pedagogical and extended version of the results published in Refs. [1,2] and presented by the authors in various talks during the last year. We discuss the type II D-branes (both regular and fractional) of the orbifold…
In the context of F-theory, we study the related eight dimensional super-Yang-Mills theory and reveal the underlying supersymmetric quantum mechanics algebra that the fermionic fields localized on the corresponding defect theory are related…
We introduce a new class of non-compact backgrounds of Type IIB string theory preserving eight supercharges by combining S-folds and non-perturbative 7-branes wrapping orbifolds, and study the four-dimensional superconformal field theories…
In this work, motivated by Laplacian type center gauges in the lattice, designed to avoid the Gribov problem, we introduce a new family of gauge fixings for pure Yang-Mills theories in the continuum. This procedure separates the partition…
In this letter, an alternative string theory in twistor space is proposed for describing perturbative N=4 super-Yang-Mills theory. Like the recent proposal of Witten, this string theory uses twistor worldsheet variables and has manifest…
Fluxbrane-like backgrounds obtained from flat space by a sequence of T-dualities and shifts of polar coordinates (beta deformations) provide an interesting class of exactly solvable string theories. We compute the one-loop partition…
Seiberg-Witten solutions of four-dimensional supersymmetric gauge theories possess rich but involved integrable structures. The goal of this paper is to show that an isomonodromy problem provides a unified framework for understanding those…