Related papers: Twistor Strings with Flavour
In this letter a new class of twisted strings is presented, with an asymmetry between the holomorphic and antiholomorphic sectors parametrized by an integer $N$. Their physical content is given by the massless resonances of the closed…
It is shown that two dimensional (2d) topological gravity in the conformal gauge has a larger symmetry than has been hitherto recognized; in the formulation of Labastida, Pernici and Witten it contains a twisted ``small'' N=4 superconformal…
We investigate the tree-level S-matrix in gauge theories and open superstring theory with several soft particles. We show that scattering amplitudes with two or three soft gluons of non-identical helicities behave universally in the limit,…
We consider topological twisting of recently constructed Chern-Simons-matter theories in three dimensions with N=4 or higher supersymmetry. We enumerate physically inequivalent twistings for each N, and find two different twistings for N=4,…
We reformulate twistor-string theory as a heterotic string based on a twisted (0,2) model. The path integral localizes on holomorphic maps, while the (0,2) moduli naturally correspond to the states of N=4 super Yang-Mills and conformal…
Some implications of flavour unification in supersymmetric Grand Unified Theories are briefly reviewed. We argue that the gauge hierarchy phenomenon properly interpreted in terms of the natural missing VEV solution for the adjoint scalar in…
We study duals to field theories in two dimensions with N=(4,4) SUSY. The string backgrounds reproduce certain non-perturbative aspects of the dual field theory with a large number of colors N_c and a tunable number of flavors N_f.…
A generalized twistor transform for spinning particles in 3+1 dimensions is constructed that beautifully unifies many types of spinning systems by mapping them to the same twistor, thus predicting an infinite set of duality relations among…
We study a class of four-dimensional $\mathcal{N}=2$ SU($N$) gauge theories with two massless hypermultiplets in the rank-two antisymmetric representation and $0\leq N_f\leq 4$ fundamental flavors. These theories are superconformal for…
We study the topologically twisted index of 3d $\mathcal{N}=2$ supersymmetric gauge theories with unitary gauge groups. We implement a Gr\"obner basis algorithm for computing the $\Sigma_g\times S^1$ index explicitly and exactly in terms of…
We discuss R-symmetries in locally supersymmetric N=2 gauge theories coupled to hypermultiplets which can be thought of as effective theories of heterotic superstring models. In this type of supergravities a suitable R-symmetry exists and…
We present the evidence for two conjectures related to the twistor string. The first conjecture states that two super-Calabi Yaus -- the supertwistor space and the superambitwistor space -- form a mirror pair. The second conjecture is that…
We discuss gauge theories on D3 branes embedded in special non-tachyonic orientifolds of the 0B string theory. In general, they correspond to non-supersymmetric SU(N) gauge theories with scalars in the adjoint representation and spinors in…
It was recently shown that the string theory duals of certain deformations of the N=4 gauge theory can be obtained by a combination of T-duality transformations and coordinate shifts. Here we work out the corresponding procedure of twisting…
In this Ph. D. Thesis we concentrate on the study of the extension of the AdS/CFT correspondence to theories with less supersymmetry. In particular, we search for the possibility of adding supersymmetric D-branes in type IIB supergravity…
We study some aspects of the recently discovered connection between dimer models and D-brane gauge theories. We argue that dimer models are also naturally related to closed string theories on non compact orbifolds of $\BC^2$ and $\BC^3$,…
We investigate generalised global symmetries in 3d $\mathcal{N}=4$ orthosymplectic quiver gauge theories. Using the superconformal index, we identify a $D_8$ categorical symmetry web in a class of theories featuring $\mathfrak{so}(2N)…
Witten's topological B-model on a Calabi-Yau background is known to reproduce, in the open string sector, the derived category of coherent sheaves. When the target space is a complex torus, the topological model enjoys a non-geometric…
We construct a realistic Supersymmetric Grand Unified Theory of Flavour based on PSL(2,7) x SO(10), where the quarks and leptons in the 16 of SO(10) are assigned to the complex triplet representation of PSL(2,7), while the flavons are…
The F-theory background of four D7 branes in a type I' orientifold was conjectured to be described by the Seiberg-Witten curve for the superconformal SU(2) gauge theory with four flavors. This relation was explained by considering in this…