Dynamical Gauge Bosons and Grand Unified Theory

Abstract

We propose that the difference of dynamical gauge bosons in asymptotically non-free (ANF) gauge thoeries from elementary ones is the existence of the compositeness condition at some scale $Lambda$. This shall be explained by using non-linear Grassmannian like model where dynamical gauge bosons are generated associated with the hidden local symmetry. Then we argue that ANF gauge theories may provide another possible scenario of the ``standard model'' below GUT scale, where we shall see that infra-red stable points play essential roles. The talk is based on the papers written with J. Sato and K. Yoshioka, T. Takeuchi, T. Onogi and Y. Taniguchi and S. Tanimura (Invited talk at SCGT workshop held in Nagoya in Novenber 1996).