Testing Extended Technicolor With $R_b$

Abstract

We review the connection between $m_t$ and the $Zb\bar{b}$ vertex in ETC models and demonstrate the power of the resulting experimental constraint on models with weak-singlet ETC bosons. Some efforts to bring ETC models into agreement with experimental data on the $Zb\bar{b}$ vertex are mentioned, and the most promising one (non-commuting ETC) is discussed in detail.

Comments: Talk given by E.H. Simmons at the Yukawa International Seminar `95 in Kyoto, 21-26 August, 1995 and at the International Symposium on Heavy Flavor and Electroweak Theory in Beijing, 17-19 August, 1995. Latex (uses PTPTeX.sty and epsf). 9 pages. 1 figure. Full postscript version available at http://smyrd.bu.edu/ . (minor typos corrected)