  The first half is a rapid review of 30 years of work on physics in anti-De
Sitter space, with heavy emphasis on singletons. Principal topics are the
kinematical basis for regarding singletons as the constituents of massless
particles, and the effect of (negative) curvature in the infrared domain. Ideas
that lead to an alternative to Big Bang cosmology are merely sketched. The
second half presents new ideas inspired by experimental results on neutrino
oscillations. Since leptons are massless before symmetry breaking it is natural
to view them as composite states consisting of one Bose singleton (the Rac) and
one Fermi singleton (the Di). This gives rise to a particular formulation of
the phenomenology of electroweak physics, and strong suggestions for an
expansion of the Standard model. An expansion of the Higgs sector seems
inevitable, and flavor changing symmetry, complete with a new set of heavy
vector mesons, is a very attractive possibility.
