Related papers: Values of the Couplings and Internal Geometry
Anomalous U(1) gauge symmetries can appear both in heterotic and type I string theories. In the heterotic case we find a single anomalous U(1), while in open string theories several such symmetries can appear. Nonetheless, there is a…
In a recent paper [1] we showed that N=1 supersymmetric QCD in the presence of certain superpotential deformations has a rich landscape of supersymmetric and non-supersymmetric vacua. In this paper we embed this theory in string theory as a…
We explain, in a slightly modified form, an old construction allowing to reformulate the U(N) gauge theory defined on a D-dimensional lattice as a theory of lattice strings (a statistical model of random surfaces). The world surface of the…
We address the effect of an anomalous triple gauge boson couplings on a physical observable for the electroweak sector of the Standard Model, when the $SU(2)_{L}\otimes U(1)_{Y}$ symmetry is spontaneously broken by the Higgs mechanism to…
Relations between the global structure of the gauge group in elliptic F-theory compactifications, fractional null string junctions, and the Mordell-Weil lattice of rational sections are discussed. We extend results in the literature, which…
The explanation of the photoelectric effect by Einstein and Maxwell's field theory of electromagnetism have motivated De Broglie to make the hypothesis that matter exhibits both waves and particles like-properties. These representations of…
In some models of N=1 supersymmetric SU(M) gauge dynamics (hep-th/9503163 and hep-th/9707244), the tension of a string ending on q external quarks is proportional to sin(pi q/M), q=1,..., M-1. In this paper we calculate the ratios of the…
1. Preliminaries. 2. Heterotic string and motivations for large volume compactifications; 2.1 Gauge coupling unification; 2.2 Supersymmetry breaking by compactification. 3. M-theory on S^1/Z_2 \times Calabi-Yau. 4. Type I/I' string theory…
We consider a Kaluza-Klein theory whose ground state is ${\bf R}^4 \times {\bf M } \times {\bf K}$ where ${\bf M}$ and ${\bf K}$ are compact, irreducible, homogenous internal mani folds. This is the simplest ground state compatible with the…
We calculate the low-lying glueball spectrum, some string tensions and some properties of topology and the running coupling for SU(N) lattice gauge theories in 3+1 dimensions. We do so for N = 2,3,...12, using lattice simulations with the…
In this talk we discuss the need to introduce a string theory in order to obtain a consistent quantum theory of gravity unified with gauge interactions. We then discuss some basic properties of string theory and the origin and the…
We explicitly show the analogy between the symmetry breaking scheme for the GUT flipped $SU(5)$ with that of the Weinberg-Salam theory of electroweak interactions. This allows us to construct the embedded defect spectrum of the theory…
We calculate the gauge couplings in the dual standard model. These values are consistent with an associated GeV mass scale, and predict the weak mixing angle to be ${\sin^2 \theta_w} (M_Z) \sim 0.22$.
The U(N) gauge theory on a D-dimensional lattice is reformulated as a theory of lattice strings (a statistical model of random surfaces). The Boltzmann weights of the surfaces can have both signs and are tuned so that the longitudinal modes…
We discuss string theory relations between gravity and gauge theory tree amplitudes. Together with $D$-dimensional unitarity, these relations can be used to perturbatively quantize gravity theories, i.e. they contain the necessary…
Particles that are heavy compared to the electroweak scale ($M \gg m_W$), and that are charged under electroweak SU(2) gauge interactions display universal properties such as a characteristic fine structure in the mass spectrum induced by…
In string theory the coupling ``constants'' appearing in the low-energy effective Lagrangian are determined by the vacuum expectation values of some (a priori) massless scalar fields (dilaton, moduli). This naturally leads one to expect a…
We show how U(1) lattice gauge theories display key signatures of ergodicity breaking in the presence of a random charge background. Contrary to the widely studied case of spin models, in the presence of Coulomb interactions, the spectral…
A generic lesson of string theory is that the coupling constants of an effective low energy theory are determined by the vacuum values of a set of fields - the so-called moduli - some of which are stabilized at relatively low masses by…
It is illustrated that quantum nucleardynamics (QND) as an SU(2)_N x U(1)_Z gauge theory, which is generated from quantum chromodynamics (QCD) as an SU(3)_C gauge theory through dynamical spontaneous symmetry breaking, successfully…