Editing Proton decay (section)

== Experimental evidence ==
Proton decay is one of the key predictions of the various grand unified theories (GUTs) proposed in the 1970s, another major one being the existence of [[magnetic monopoles]]. Both concepts have been the focus of major experimental physics efforts since the early 1980s. To date, all attempts to observe these events have failed; however, these experiments have been able to establish lower bounds on the half-life of the proton.  Currently, the most precise results come from the [[Super-Kamiokande]] water [[Cherenkov radiation]] detector in Japan:<ref>
{{cite journal
 |last1 = Mine           |first1 = Shunichi
 |year = 2023
 |title = Nucleon decay: theory and experimental overview
 |journal = Zenodo
 |doi = 10.5281/zenodo.10493165
}}
</ref> a lower bound on the proton's half-life of {{val|2.4|e=34|u=years}} via positron decay, and similarly, {{val|1.6|e=34|u=years}} via [[antimuon]] decay, close to a supersymmetry (SUSY) prediction of 10<sup>34</sup>–10<sup>36</sup>&nbsp;years.<ref>{{Cite web |date=25 November 2009 |title=Proton lifetime is longer than 10<sup>34</sup> years |url=http://www-sk.icrr.u-tokyo.ac.jp/whatsnew/new-20091125-e.html |url-status=dead |archive-url=https://web.archive.org/web/20110716144726/http://www-sk.icrr.u-tokyo.ac.jp/whatsnew/new-20091125-e.html |archive-date=16 July 2011 |website=[[Kamioka Observatory]]}}</ref> An upgraded version, [[Hyper-Kamiokande]], probably will have sensitivity 5–10 times better than Super-Kamiokande.