相关论文: Dynamical Gauge Coupling Constants

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…

String theory predicts that the couplings of Nature descend from dynamical fields. All known string-motivated particle physics models also come with a wide range of possible extra sectors. It is common to posit that such moduli are frozen…

We briefly discuss the differences between considering the gauge coupling as a constant or as a field, the dilaton, in N=1 supersymmetric theories. We emphasize the differences regarding supersymmetry breaking. Recent developments on the…

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…

String theory, if it describes nature, is probably strongly coupled. As a result, one might despair of making any statements about the theory. In the framework of a set of clearly spelled out assumptions, we show that this is not…

A strong-weak coupling duality symmetry of the string equations of motion has been suggested in the literature. This symmetry implies that vacua occur in pairs. Since the coupling constant is a dynamical variable in string theory, tunneling…

In the context of the field theory limit of superstrings, we consider an almost realistic model of supersymmetry breaking by gaugino condensation which includes, through nonperturbative corrections to the K\"ahler potential, dilaton…

We investigate the field dependence of the gauge couplings of $N=1$ string vacua from the point of view of the low energy effective quantum field theory. We find that field-theoretical considerations severely constrain the form of the…

There are only a small number of ideas for stabilizing the moduli of string theory. One of the most appealing of these is the racetrack mechanism, in which a delicate interplay between two strongly interacting gauge groups fixes the value…

New recent results in supersymmetric gauge theories based on holomorphy and symmetry considerations are extended to the case where the gauge coupling constant is given by the real part of a chiral superfield. We assume here that its…

In this paper we conduct a general, model-independent analysis of the running of gauge couplings within closed string theories. Unlike previous discussions in the literature, our calculations fully respect the underlying modular invariance…

We use recently obtained 2-loop string coupling constants to analyze a class of string models based on orbifold compactification. Assuming weak coupling at the string scale and single-scale unification leads to restrictions on the spectrum…

Ideas about a duality between gauge fields and strings have been around for many decades. During the last ten years, these ideas have taken a much more concrete mathematical form. String descriptions of the strongly coupled dynamics of…

The ground state of string theory may lie at a point of ``maximally enhanced symmetry", at which all of the moduli transform under continuous or discrete symmetries. This hypothesis, along with the hypotheses that the theory at high…

In this note we display an observation about the geometrical properties of the gauge group manifold of the standard electroweak theory, and the values of the gauge coupling constants. Heuristically obtained stucture relates the value…

A distinctive feature of string unification is the possibility of unification by a non-simply-laced group. This occurs most naturally in four dimensional type~II string models where the gauge symmetry is realized by Kac-Moody algebras at…

Some recent developments in the weakly-coupled heterotic string phenomenology are reviewed. We discuss several important issues such as dilaton/moduli stabilization, supersymmetry breaking (by hidden-sector gaugino condensation), gauge…

String theory, if it describes nature, is probably strongly coupled. In light of recent developments in string duality, this means that the ``real world'' should correspond to a region of the classical moduli space which admits no weak…

I discuss several aspects of strings as unified theories. After recalling the difficulties of the simplest supersymmetric grand unification schemes I emphasize the distinct features of string unification. An important role in constraining…

I discuss some current thoughts on how low-energy measurements and consistency constrain theories at high energies with emphasis on string theory. I also discuss some recent work on the dynamics of supersymmetric gauge theories.