Tri-Maximal vs Bi-Maximal Neutrino Mixing

Abstract

It is argued that data from atmospheric and solar neutrino experiments point strongly to tri-maximal or bi-maximal lepton mixing. While (`optimised') bi-maximal mixing gives an excellent a posteriori fit to the data, tri-maximal mixing is an a priori hypothesis, which is not excluded, taking account of terrestrial matter effects.

6 Pages in LaTeX, 8 Figures as postscript files. (This is the written version of a talk given at the Sixth Topical Seminar on Neutrino and Astro-Particle Physics, held 17-21 May 1999, San Miniato, Italy.) Version-2 corrects a typo interchanging omega and omega-bar in the 2nd matrix of Eq. 1