HEP
In the literature: open
Does the proton decay to an antineutrino and a kaon?
In plain words
Supersymmetric unified theories favor a different decay of the proton, into an antineutrino and a charged kaon. Detecting the kaon needs detectors with good tracking.
Precise statement
Measure or bound tau(p -> anti-nu K+)/B, currently $> \sim 5.9e33\,\mathrm{yr}$ (Super-Kamiokande, 2014). Minimal SUSY $\mathrm{SU}(5)$ with dimension-5 operators predicts values near or below this; an answer is a detection or a limit $\sim 1e34\text{ to }1e35\,\mathrm{yr}$.
What would settle it
DUNE liquid-argon tracking, Hyper-Kamiokande and JUNO searches for p -> anti-nu K+.
Related problems
- Special case of Do the SM gauge forces unify into a single group?