Gauge model for maximal neutrino mixing

The recently announced Super-Kamiokande data on atmospheric neutrino oscill ation seems to require a maximal mixing between the nu(mu) and nu(tau) with in the conventional three neutrino picture. It is then tempting to suggest as has been done in literature, that the solar neutrino deficit be also und erstood as resulting from a maximal mixing between nu(e) and nu(mu). In thi s letter, we propose a left-right symmetric extension of the standard model where permutation symmetry leads to one of the maximal mixing patterns in a technically natural manner. The double seesaw mechanism gives small Major ana masses for neutrinos needed to understand the atmospheric as well as th e solar neutrino puzzles. (C) 1998 Elsevier Science B.V. All rights reserve d.