# Neutrino masses

- kind: problem
- status: partial
- year: 1957

**Statement.** What are the neutrino masses, how are they ordered, and are neutrinos their own antiparticles?

The Standard Model had neutrinos massless. Oscillations showed they are not, which earned the 2015 Nobel Prize, and the solar neutrino problem was resolved along the way. The absolute masses, their ordering, and whether neutrinos are Majorana particles remain open. KATRIN bounds the mass below 0.45 eV.

Closed 1998, Super-Kamiokande: neutrinos oscillate, so they have mass.

## Related problems

- The original curation links this problem to [The solar neutrino problem](/wiki/Problem:solar-neutrino-problem.md); the argument for the link has not been written yet.

## Sources

- [Wikipedia: Neutrino oscillation](https://en.wikipedia.org/wiki/Neutrino_oscillation)

[The Standard Model's loose ends](/wiki/Space:standard-model.md) · [Physics](/wiki/Continent:physics.md)

## Relations

- related to [solar-neutrino-problem](/wiki/Problem:solar-neutrino-problem.md) — The original curation links this problem to The solar neutrino problem; the argument for the link has not been written yet.

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