The Leptons After 100 Years

OCT 01, 1997

Puzzles and mysteries abound: Are there more than just the six leptons already known; what is the intrinsic difference between the electron, the muon and the tau; do neutrinos have mass?

DOI: 10.1063/1.881960

Martin L. Perl

Over the course of a century, six leptons have been discovered in the universe of elementary particles. Three—the electron, muon and tau—each have one unit of electric charge; the other three—the neutrinos—have no charge.

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More about the Authors

Martin L. Perl. Stanford Linear, Accelerator Center, Stanford, California.