Neutrino Cosmology and Limits on Extended Technicolor

Abstract

Using Big Bang Nucleosynthesis limits on the number of light neutrinos we derive a cosmological lower bound of $\approx 2$ TeV on the scale of extended technicolor interactions (or any other new interactions) for the third family in models where heavy gauge bosons couple to both left and right-handed neutrinos.

Comments: 12 pages plus one figure (not included, available as ps file from Krauss), YCTP-P8-93