Whereas SU 5 was as simple as possible, researchers have found a variety of other symmetry groups that the existing particles might fit into, with extra features and variables that can make protons decay much more slowly. It might start seeing a trickle of decays. Or it might not. One of these models might be correct, but no one would ever know.
Glashow, for one, largely lost interest in the whole affair when SU 5 was ruled out. The circumstantial evidence is as compelling as ever.
But the idea could remain in perpetual limbo, rather like the proton. This article was reprinted on Wired. Get highlights of the most important news delivered to your email inbox. Quanta Magazine moderates comments to facilitate an informed, substantive, civil conversation. Abusive, profane, self-promotional, misleading, incoherent or off-topic comments will be rejected.
Moderators are staffed during regular business hours New York time and can only accept comments written in English. Babu is fond of a GUT that shares many of the advantages of the supersymmetric versions. The theory includes important features absent from the Standard Model such as neutrino masses, and might explain why there is more matter than antimatter in the cosmos.
Naturally, it predicts proton decay. The reason may simply be that protons rarely decay, a hypothesis borne out by both experiment and theory.
For reference, the universe is only Protons on average will outlast every star, galaxy and planet, even the ones not yet born. Because of quantum physics, the time any given proton decays is random, so a tiny fraction will decay long before that 10 34 -year lifetime.
The second essential step is to isolate the experiment from particles that could mimic proton decay, so any realistic proton decay experiment must be located deep underground to isolate it from random particle passers-by.
The upcoming Deep Underground Neutrino Experiment, to be located in a former gold mine in South Dakota, will consist of 40, tons of liquid argon.
Because the two experiments are based on different types of atoms, they are sensitive to different ways protons might decay, which will reveal which GUT is correct … if any of the current models is right. Another possibility is that the beam and bottle approaches have been measuring the neutron lifetime correctly, but that some unseen factor accounts for the discrepancy between the two. In the meantime, the NIST beam experiment has been gathering fresh data since last year, using sensitive detectors and other components that will make it more precise than previous runs — measuring the neutron lifetime to within one second rather than three to four seconds as has happened so far.
And the team is already designing its next-generation experiment, which aims to nail the neutron lifetime within 0. Pattie, R. Jr et al. Science , — PubMed Article Google Scholar.
Ezhov, V. JETP Lett. Article Google Scholar. Serebrov, A. C 97 , Yue, A. Fornal, B. Paid quarterly Inclusive of applicable taxes VAT. Trending Latest Video Free. A fragment of our moon may be orbiting the sun with Earth Our Human Story newsletter: The patterns of domestication Sterile neutrinos could explain dark matter — if we can find them COP New alliance commits to ending oil and gas extraction Covid news: Coronavirus deaths in Europe rise 10 per cent in a week.
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