Related papers: Kaehler Metrics and Yukawa Couplings in Magnetized…

We extend the general solution to the Cauchy problem for the relativistic closed string (Phys. Lett. B404 (1997) 57-65, hep-th/9704084) to the case of open strings attached to Dp-branes, including the cases where the initial data has a…

We study the dynamics of an open membrane with a cylindrical topology, in the background of a constant three form, whose boundary is attached to p-branes. The boundary closed string is coupled to a two form potential to ensure gauge…

Why adding a collinear magnetic field to the electric one on a D3 brane in a system of two parallel separated D3 branes can enhance the open string pair production? How is the open string pair production rate related to the QED ones in the…

An analysis of a special class of type II string theory compactifications is presented. We focus on recent work in one particular orientifold background of intersecting brane models and the resulting four dimensional gauge group and matter…

The perturbative leading order open string three-point couplings for the Standard Model with hidden USp(6) on fractional D6-branes on T6/Z6' from arXiv:0806.3039 [hep-th], arXiv:0910.0843 [hep-th] are computed. Physical Yukawa couplings…

In a classic paper, Fradkin and Tseytlin showed how magnetic deformations can be introduced in open strings. In this contribution we review some recent work on type-I vacua with magnetised branes and describe the role of additional discrete…

One of the challenges of heterotic compactification on a Calabi-Yau threefold is to determine the physical $(\mathbf{27})^3$ Yukawa couplings of the resulting four-dimensional $\mathcal{N}=1$ theory. In general, the calculation necessitates…

We study the effect of adding charged matter fields to both D3 and D7 branes in type IIB string theory compactification with fluxes. Generically, charged matter fields induce additional terms to the Kahler form, the superpotential and the…

We discuss the sigma model description of a D-string bound to k D-fivebranes in type I string theory. The effective theory is an (0,4) supersymmetric hyper-Kahler with torsion sigma model on the moduli space of Sp(k) instantons on R^4. Upon…

In a recent paper we have proposed the possibility that the lightest massive string states could be identified with open strings living at intersections of D-branes forming small angles. In this note, we reconsider the relevant twist-field…

This thesis investigates correspondences between open and closed strings. This is done on the level of coupled open-closed moduli spaces and from a string field theoretic point of view. The construction of boundary string field theory on…

We study conformal field theory correlation functions relevant for string diagrams with open strings that stretch between several parallel branes of different dimensions. In the framework of conformal field theory, they involve boundary…

We study the dynamics of a D3 brane in generic IIB warped compactifications, using the Hamiltonian formulation discussed in arXiv:0805.3700 [hep-th]. Taking into account of both closed and open string fluctuations, we derive the warped…

We study Dirac commutators of canonical variables on D-branes with a constant Neveu-Schwarz 2-form field by using the Dirac constraint quantization method, and point out some subtleties appearing in previous works in analyzing constraint…

We systematically search intersecting D-brane models, which just realize the Standard Model chiral matter contents and gauge symmetry. We construct new classes of non-supersymmetric Standard Model-like models. We also study gauge coupling…

Finding the exact, quantum corrected metric on the hypermultiplet moduli space in Type II string compactifications on Calabi-Yau threefolds is an outstanding open problem. We address this issue by relating the quaternionic-Kahler metric on…

Calabi--Yau compactifications of the $E_8\times E_8$ heterotic string provide a promising route to recovering the four-dimensional particle physics described by the Standard Model. While the topology of the Calabi--Yau space determines the…

We study the realization of non-Abelian discrete gauge symmetries in 4d field theory and string theory compactifications. The underlying structure generalizes the Abelian case, and follows from the interplay between gaugings of non-Abelian…

We investigate the consequences of generalizing certain well established properties of the open string metric to the conjectured open membrane and open Dp-brane metrics. By imposing deformation independence on these metrics their functional…

We show how the brane wrapping rules, recently discovered in closed oriented string theories compactified on tori, are extended to the case of the Type IIA string compactified on K3. To this aim, a crucial role is played by the duality…