Neutrino Mass: Where Do We Stand, and Where Are We Going?

TL;DR

This paper reviews current evidence for neutrino mass from atmospheric, solar, and LSND experiments, discusses proposed mass scenarios, and outlines future tests needed to confirm and understand neutrino properties.

Contribution

It provides a comprehensive overview of neutrino mass hints and proposes future experimental directions to clarify neutrino mass mechanisms.

Findings

Strong evidence of neutrino mass from atmospheric neutrinos

Promising hints from solar neutrino observations

Unconfirmed LSND neutrino oscillation hint

Abstract

We discuss the three major hints of neutrino mass: the strong evidence of mass from the behavior of atmospheric neutrinos, the very promising further hint from the behavior of solar neutrinos, and the so-far unconfirmed hint from the LSND experiment. Then, we describe two illustrative neutrino-mass scenarios suggested by the observed hints. We identify the needed future tests of both the present hints and the neutrino-mass scenarios.