相关论文: Kinetic mixing of U(1)s for local string models

Tests of duality between heterotic strings on $K3\times T^2$ (restricted on certain Narain moduli subspaces) and type IIA strings on K3-fibered Calabi-Yau threefolds are attempted in the weak coupling regime on the heterotic side by…

The spontaneous emergence of coherent structures from chaotic backgrounds is a hallmark of active biological swarms. We investigate this self-organization by simulating an ensemble of polar chiral active agents that couple locally via a…

We compute the one-loop gauge couplings in six-dimensional non-Abelian gauge theories on the T^2/Z_2 orbifold with general GUT breaking boundary conditions. For concreteness, we apply the obtained general formulae to the gauge coupling…

Recent scenarios of phenomenologically realistic string compactifications involve the existence of gauge sectors localized on D-branes at singular points of Calabi-Yau threefolds. The spectrum and interactions in these gauge sectors are…

We consider gauge coupling unification in models with TeV scale strings and large compact dimensions realized as type IIB string orientifolds. Following an observation by Ibanez we show that the gauge couplings at low energies can behave as…

It is shown that for small relative angle and kinetic energy two type I $U(1)$ strings can form bound states upon collision instead of the more familiar intercommuting configuration. The velocity below which this may happen is estimated as…

The string one loop renormalization of the gauge coupling constants is examined in abelian orbifold models. The contributions to string threshold corrections independent of the compactification moduli fields are evaluated numerically for…

It has long been known that strings wound around incontractible cycles can play a vital role in cosmology. In particular, in a spacetime with toroidal spatial hypersurfaces, the dynamics of the winding modes may help yield three large…

We investigate both geometric and conformal field theoretic aspects of mirror symmetry on N=(4,4) superconformal field theories with central charge c=6. Our approach enables us to determine the action of mirror symmetry on (non-stable)…

We discuss UV/IR mixing effects in non-supersymmetric non-commutative U(N) gauge theories. We show that the singular (non-planar) terms in the 2- and 3-point functions, namely the poles and the logarithms, can be obtained from a manifestly…

We analyze a structure of dynamical chiral symmetry breaking in orbifold gauge theories with matter fields (fermions) on the fixed point. We find that the boundary chiral phase structure of QED and QCD on the orbifold is quite nontrivial…

We discuss models of neutrino masses that lead to a large mixing angle for atmospheric neutrino oscillations. In particular we study a mechanism where a simple texture for the Dirac matrix leads to the observed pattern of mixings for a…

We analyze the nonlinear waves that propagate on a microtubule that is tethered at its minus end due to kinesin walking on it, as is seen during the fluid mixing caused by cytoplasmic streaming in Drosophila oocytes.The model we use assumes…

We analyse a class of four-dimensional heterotic ground states with N=2 space-time supersymmetry. From the ten-dimensional perspective, such models can be viewed as compactifications on a six-dimensional manifold with SU(2) holonomy, which…

We numerically solve the equations of motion (EOM) for two models of circular cosmic string loops with windings in a simply connected internal space. Since the windings cannot be topologically stabilized, stability must be achieved (if at…

We discuss consistency conditions for branes at orbifold singularities. The conditions have a world-sheet interpretation in terms of tadpole cancellation and a space-time interpretation in terms of anomalies. As examples, we consider type…

We apply the standard approach of RG flow for the gauge couplings in N=1 D=4 Supergravity to show how to match its results with the heterotic $Z_3$ orbifold and Type IIB ${Z_3}$ orientifold-based models. Using only supergravity, anomaly…

We propose a bottom-up approach to the building of particle physics models from string theory. Our building blocks are Type II D-branes which we combine appropriately to reproduce desirable features of a particle theory model: 1) Chirality…

Brane tilings provide the most general framework in string and M-theory for matching toric Calabi-Yau singularities probed by branes with superconformal fixed points of quiver gauge theories. The brane tiling data consists of a bipartite…

Intersecting D6-branes provide a geometrically intuitive road to stringy particle physics models, where D6-branes stuck at orbifold singularities can lead to the stabilisation of deformation moduli, and the QCD axion can arise from the open…