LHC@home

The proton, a particle found at the heart of every atom, appears to have a more complicated structure than is traditionally given in textbooks. The find could have ramifications for sensitive particle physics experiments like the Large Hadron Collider (LHC).

https://www.newscientist.com/article/2334076-physicists-surprised-to-discover-the-proton-contains-a-charm-quark/

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The article speaks of a possible charm-anticharm pair inside a proton. I suspect that would likely be a virtual pair, but I'm "only" a cosmologist, so I'm just guessing.
Another possibility, though I think probably far less likely, is up-charm quark oscillation, similar to neutrino oscillation in electro-weak. Maybe... though again, what do I know?

Either way, however, this result, if verified, will certainly mark the dawn of a very exciting new era in elementary particle theory. Oh, how I wish I was 50 years younger!!