Physicists Discover Exotic, New ‘Tetraquark’ Particle We’ve Never Seen Before

There’s a new exotic subatomic particle on the atom smasher. Physicists working with CERN’s Large Hadron Collider beauty (LHCb) collaboration have found a new form of the elusive four-quark particle called a tetraquark that they have never seen before.

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Tau.Neutrino said:

Physicists Discover Exotic, New ‘Tetraquark’ Particle We’ve Never Seen Before

There’s a new exotic subatomic particle on the atom smasher. Physicists working with CERN’s Large Hadron Collider beauty (LHCb) collaboration have found a new form of the elusive four-quark particle called a tetraquark that they have never seen before.

more…

read that

been thinking about the idea lately of there only being one electron in the universe, so went revisited that subject via wiki, no idea why, not really, a useless contemplation perhaps. I may have been considering if encoders, of replicators, and computation more broadly, allow some view back in time, some magic, a trick

https://en.wikipedia.org/wiki/One-electron_universe

“The one-electron universe postulate, proposed by John Wheeler in a telephone call to Richard Feynman in the spring of 1940, is the hypothesis that all electrons and positrons are actually manifestations of a single entity moving backwards and forwards in time……

……The idea is based on the world lines traced out across spacetime by every electron. Rather than have myriad such lines, Wheeler suggested that they could all be parts of one single line like a huge tangled knot, traced out by the one electron. Any given moment in time is represented by a slice across spacetime, and would meet the knotted line a great many times. Each such meeting point represents a real electron at that moment.

At those points, half the lines will be directed forward in time and half will have looped round and be directed backwards. Wheeler suggested that these backwards sections appeared as the antiparticle to the electron, the positron.

Many more electrons have been observed than positrons, and electrons are thought to comfortably outnumber them. According to Feynman he raised this issue with Wheeler, who speculated that the missing positrons might be hidden within protons.

Feynman was struck by Wheeler’s insight that antiparticles could be represented by reversed world lines…”

> “The one-electron universe postulate, proposed by John Wheeler in a telephone call to Richard Feynman in the spring of 1940, is the hypothesis that all electrons and positrons are actually manifestations of a single entity moving backwards and forwards in time……

I’m not buying that.

Tau.Neutrino said:

Physicists Discover Exotic, New ‘Tetraquark’ Particle We’ve Never Seen Before

There’s a new exotic subatomic particle on the atom smasher. Physicists working with CERN’s Large Hadron Collider beauty (LHCb) collaboration have found a new form of the elusive four-quark particle called a tetraquark that they have never seen before.

more…

OK, just as a meson is made of one quark and its antiparticle bound together, a tetraquark can be made from two quarks and their antiquarks bound together. There’s nothing in quantum physics to forbid this. Not too surprisingly, when a particle is bound to its antiparticle, the result doesn’t have a very long half life.

> Two charm quarks and two charm antiquarks.
> Up until now, the LHCb and other experiments had only observed tetraquarks with two heavy quarks at most, and none with more than two quarks of the same type.

That’s strange or, rather, not strange. Where are the tetraquarks made from strange quarks? Strange quarks are lighter than charm quarks so should be around for longer and easier to spot.

> The team combed over this data using a new technique for looking for new particles that involves searching for an excess in collision events. The researchers found this excess for a type of particle called a J/ψ meson, which consists of two quarks – a charm quark and a charm antiquark.

> J/ψ meson are, like all mesons, unstable; they decay in less than a zeptosecond, which means they’re challenging to detect directly. What we can detect is the muon particles that J/ψ mesons decay into, and infer their presence that way. But the muon particle showers the team detected were too energetic for simple decay of J/ψ mesons. Interestingly, however, they were right smack-bang in the middle of the energy range predicted for fully charmed tetraquarks (as the type of particle is rather charmingly known), within the standard deviation threshold for claiming the discovery of a new particle.

I like that. “Fully charmed tetraquarks”.