Higgs and Top quark coupled with a conformal gauge sector

We propose a dynamical scenario beyond the standard model, in which the radiative correction to the Higgs mass parameter is suppressed due to a large anomalous dimension induced through a conformal invariant coupling with an extra gauge sector. Then the anomalous dimension also suppresses the Yukawa couplings of the Higgs field. However, the large top Yukawa coupling can be generated effectively through mixing among top quarks and the fermions of the conformal gauge sector. This scenario is found to predict a fairly heavy Higgs mass of about 500 GeV. We present an explicit model and show consistency with the Electro-Weak precision measurements of the S and T parameters as well as the Z boson decay width.Comment: 12 pages, 3 Postscript figures, uses RevTex.sty; corrected typos and reference

Two Dimensional Black Hole Evapolation in the Light-Cone Gauge

Quantization of the pure $1+1$ dimensional dilaton gravity is examined in the light-cone gauge. It is found that the total action including ghosts generates a $c=0$ free conformal field theory without modification of the classical action, which is required in the conformal gauge. We also study semiclassical equations of the dilaton gravity coupled to $N$ scalar fields. It is shown that the black hole singularity is not removed even for $N<24$ in the light-cone gauge. This indicates that the semiclassical analysis breaks down for small $N$.Comment: 10 pages, KANAZAWA-92-1

Equivalent models for gauged WZW theory

We modify the $SL(2,{\bf R})/U(1)$ WZW theory, which was shown to describe strings in a 2D black hole, to be invariant under chiral $U(1)$ gauge symmetry by introducing a Steukelberg field. We impose several interesting gauge conditions for the chiral $U(1)$ symmetry. In a paticular gauge the theory is found to be reduced to the Liouville theory coupled to the $c=1$ matter perturbed by the so-called black hole mass operator. Also we discuss the physical states in the models briefly.Comment: 13pages, KANAZAWA 93-0

More about Kaluza-Klein Regularization

We study the so-called ``Kaluza-Klein regularization''. We calculate one-loop corrections to the Higgs mass due to Kaluza-Klein modes explicitly in a model with SUSY breaking mass splitting between bosonic and fermionic modes. We perform the proper time cutoff at $1/\Lambda^2$ and the KK level truncation at $\ell$. It is shown that the finite result is obtained as long as $\ell \gg R\Lambda$ for the compactification radius $R$.Comment: 9 pages, latex, 2 figure

Suppressing FCNC and CP-Violating Phases by Extra Dimensions

In extra dimensions the infrared attractive force of gauge interactions is amplified. We find that this force can align in the infrared limit the soft-supersymmetry breaking terms out of their anarchical disorder at a fundamental scale, in such a way that flavor-changing neutral currents as well as dangerous CP-violating phases are sufficiently suppressed at the unification scale. The main assumption is that the matter and Higgs supermultiplets and the flavor-dependent interactions such as Yukawa interactions are stuck at the four-dimensional boundary. As a concrete example we consider the minimal model based on SU(5) in six dimensions.Comment: 9 pages, 2 figure

ERG and Schwinger-Dyson Equations - Comparison in formulations and applications --

The advantageous points of ERG in applications to non-perturbative analyses of quantum field theories are discussed in comparison with the Schwinger-Dyson equations. First we consider the relation between these two formulations specially by examining the large N field theories. In the second part we study the phase structure of dynamical symmetry breaking in three dimensional QED as a typical example of the practical applications.Comment: 13 pages, 6 figures, references are added. Invited talk presented at Second Conference on the Exact RG, Sept 18 - 22, 2000, Rome, Ital