相关论文: Prediction for $\alpha_3(M_z)$ in a string-inspire…
We look for the minimal particle content which is necessary to add to the standard model in order to have a complete unification of gauge couplings and gravity at the weakly coupled heterotic string scale. Using the current precision…
We consider gauge unification in nonminimal models with extra spacetime dimensions above the TeV scale. We study the possibility that only a a subset of the supersymmetric standard model gauge and Higgs fields live in the higher dimensional…
A way to break supersymmetry in perturbative superstring theory is the string version of the Scherk-Schwarz mechanism. There, the fermions and bosons have mass splitting due to different compactification boundary conditions. We consider the…
In the superstring models we have not only the complete {\bf 27} multiplets of $E_6$ but also extra incomplete $({\bf 27}+{\overline {\bf 27}})$ chiral supermultiplets being alive at low energies. Associated with these additional…
A SU(3) \times SU(2) \times U(1) supersymmetric theory is constructed with a TeV sized extra dimension compactified on the orbifold S^1/(Z_2 \times Z_2'). The compactification breaks supersymmetry leaving a set of zero modes which…
The Higgs quartic coupling has now been indirectly measured at the electroweak scale. Assuming no new low-scale physics, its running is known and, together with gauge and Yukawa couplings, it is a crucial new piece of information…
In the extra U(1) superstring inspired model, we examine the electroweak and U(1)-prime symmetry breaking with the singlet and exotic quark D, D+{\c}along with the study of heavy Z-prime boson in accordance with the top quark mass region.…
We consider the dimensional reductions of N=4 Supersymmetric Yang-Mills theory on R x S^3 to the three-dimensional theory on R x S^2, the orbifolded theory on R x S^3/Z_k, and the plane-wave matrix model. With explicit emphasis on the…
We study the low energy evolution of coupling constants of the standard model and show that gauge coupling unification can be achieved at the electroweak scale with a suitable normalization. We choose the grand unification group to be the…
In this talk I summarize several recent results concerning the four-dimensional effective supergravity obtained using a Calabi-Yau compactification of the $E_8\times E_8$ heterotic string from M-theory. A simple macroscopic study is…
We discuss the origin of enhanced gauge symmetry in ALE (and K3) compactification of M theory, either defined as the strong coupling limit of the type IIa superstring, or as defined by Banks et al. In the D-brane formalism, wrapped…
We investigate the region of restored electroweak symmetry around a superconducting cosmic string coupled to the Weinberg-Salam model with an extra Higgs doublet. We show that the presence of the extra Higgs fields, and in particular their…
If an extra supersymmetric U(1) gauge factor exists at the TeV energy scale, which is then broken together with the supersymmetry, there will be several interesting and important phenomenological consequences, not only at the TeV scale, but…
We examine gauge coupling unification and prediction for $\alpha_s (M_Z)$ in minimal flipped SU(5) with gauge-mediated supersymmetry breaking. We include threshold corrections at weak scale, messenger scale and unification scale, and…
Supersymmetry breaking in string perturbation theory predicts the existence of a new dimension at the TeV scale. The simplest realization of the minimal supersymmetric Standard Model in the context of this mechanism has two important…
In the absence of a tree-level scalar-field mass, renormalization-group (RG) methods permit the explicit summation of leading-logarithm contributions to all orders of the perturbative series for the effective-potential functions utilized in…
The simplest interpretation of the global success of the Standard Model is that new physics decouples well above the electroweak scale. Supersymmetric extension of the Standard Model offers the possibility of light chargino and the…
The commonly accepted notion of a weak unified coupling $\alpha_X \approx 0.04$, based on the assumption of the MSSM--spectrum, is questioned. It is suggested that the four--dimensional unified string coupling should very likely have an…
We propose a model of six dimensional $SU(7)$ grand gauge-Higgs unification compactified on $S^1/Z_2 /times S^1/Z_2$, which is a six dimensional extension of five dimensional $SU(4)$ gauge-Higgs unification predicting the weak mixing angle…
We review the construction and classification of three-family grand unified models within the framework of asymmetric orbifolds in perturbative heterotic superstring. We give a detailed survey of all such models which is organized to aid…