Will this have an impact on the Standard Model? If so, does this have any ramifications on proving or disproving any particular quantum theories?
LHCb experiment reports observation of exotic pentaquark particles
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Re: LHCb experiment reports observation of exotic pentaquark particles
#12people at cern have forgotten long ago: “Scientists study the world as it is, engineers create the world that never has been.” – Theodore von Kármán Gell Mann and Zweig among others proposed the imaginary concept of quarks (or partons, Feynman's Dolly) to do something about all those particles that kept popping up in accelerators. There was a time, when a particle was a run-of-the-mill cookie-cutter thesis.
And before that, water was made out of "water", wood was made out of "wood", and the world was a much simpler place. Your point being?
Re: LHCb experiment reports observation of exotic pentaquark particles
#13Will this have an impact on the Standard Model? If so, does this have any ramifications on proving or disproving any particular quantum theories?
No. This is analogous to finding a new molecule in chemistry, or a new isotope in nuclear physics. None of the fundamental constituents are different, they've just been been combined in a new way. (In fairness, this combination is a lot more novel than most new molecules or isotopes.) In principle, the existence of these pentaquarks could have been definitively calculated from first principles if we had sufficient computing power, just as for all molecules, but this is infeasible.
Re: LHCb experiment reports observation of exotic pentaquark particles
#14[deleted]
Re: LHCb experiment reports observation of exotic pentaquark particles
#15Will this have an impact on the Standard Model? If so, does this have any ramifications on proving or disproving any particular quantum theories?
No. This is analogous to finding a new molecule in chemistry, or a new isotope in nuclear physics. None of the fundamental constituents are different, they've just been been combined in a new way. (In fairness, this combination is a lot more novel than most new molecules or isotopes.) In principle, the existence of these pentaquarks could have been definitively calculated from first principles if we had sufficient co…
It's more than that; the mass and properties of a pentaquark will tell us a lot about the underlying properties of the strong force. People have been trying to predict the pentaquark masses and lifetimes for many years.
Computations of low-energy strong-force interactions are significantly more difficult than electromagnetism. As far as I know, the proton binding energy has not yet been calculated with confidence, though it should happen in the next decade or two.
If the result holds up, this will count as one of LHC's major discoveries.
Re: LHCb experiment reports observation of exotic pentaquark particles
#16Will this have an impact on the Standard Model? If so, does this have any ramifications on proving or disproving any particular quantum theories?
No. This is analogous to finding a new molecule in chemistry, or a new isotope in nuclear physics. None of the fundamental constituents are different, they've just been been combined in a new way. (In fairness, this combination is a lot more novel than most new molecules or isotopes.) In principle, the existence of these pentaquarks could have been definitively calculated from first principles if we had sufficient co…
Right! To put this in other words, we already had Mesons and Baryons (two- and three-quark bound states), and now we have Pentaquarks (admittedly less creative name). It's very exciting and hopefully we can learn more about QCD by observation of this and other new bound states. As jessriedel mentioned, we currently have no way to compute these states efficiently, and the computing power does not exist (yet?) to evaluate such systems on the lattice. Having this new entry in our "answer key" will hopefully lead to new insights in about the fundamentals of the strong force and/or at least some new tricks to compute bound states.
Re: LHCb experiment reports observation of exotic pentaquark particles
#17> "More precisely the states must be formed of two up quarks, one down quark, one charm quark and one anti-charm quark."
It blows my mind
Re: LHCb experiment reports observation of exotic pentaquark particles
#18Will this have an impact on the Standard Model? If so, does this have any ramifications on proving or disproving any particular quantum theories?
Not really. Pentaquarks are a prediction of the Standard Model (SM), but nicely they are a true prediction. The standard model was constructed to contain mesons (2 quarks) and hadrons (3 quarks), so the discovery of tetra and pentaquarks is a rather stringent test for predictions of the SM.
It may be, that new effects are more important for pentaquarks than for regular hadrons, since they are less well understood. Someone who works on alternate theories of the strong force can just look up all the precision measurement of the proton. If the new theory does not work there, then he will start another project. So a new particle is a rather interesting test. This is of course also true for the SM, but at the moment it looks like another brilliant confirmation.
Re: LHCb experiment reports observation of exotic pentaquark particles
#19I think the submission should link to the actual press release: http://press.web.cern.ch/press-releases/2015/07/cerns-lhcb-e...
Ok, URL changed from http://www.interactions.org/cms/?pid=1034868, which is a copy of this.
Re: LHCb experiment reports observation of exotic pentaquark particles
#20> "More precisely the states must be formed of two up quarks, one down quark, one charm quark and one anti-charm quark." It blows my mind
I find most interesting that the charm and anti-charm do not annihilate. That would not happen with non-quark particles.