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A bestiary of exotic hadrons

(cerncourier.com)
152 points rbanffy | 1 comments | 20 Dec 24 15:29 UTC | HN request time: 0s | source
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whatshisface ◴[20 Dec 24 16:02 UTC] No.42472224[source]▶
>The dynamics of quarks and gluons can be described perturbatively in hard processes thanks to the smallness of the strong coupling constant at short distances, but the spectrum of stable hadrons is affected by non-perturbative effects and cannot be computed from the fundamental theory. Though lattice QCD attempts this by discretising space–time in a cubic lattice, the results are time consuming and limited in precision by computational power. Predictions rely on approximate analytical methods such as effective field theories.

I'm glad this was mentioned, non-perturbative effects are not well understood and this is a big part of why it's worthwhile to study bound states of the strong force.

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munchler ◴[20 Dec 24 18:01 UTC] No.42473247[source]▶
I assume that if we ever unify QCD with General Relativity, the resulting theory would be able to predict these hadrons from first principles?
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ur-whale ◴[20 Dec 24 18:12 UTC] No.42473334[source]▶
> the resulting theory would be able to predict these hadrons from first principles?

Not sure how bringing GR into the fray would help solve what essentially seems to be a computational complexity problem. Might actually make things worse.

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1. whatshisface ◴[20 Dec 24 18:14 UTC] No.42473357[source]▶
It's not a computational complexity problem, it's an undefinedness problem. Proving that the lattice simulations converge has been estimated as well beyond this century's mathematics by the pair of people (Glimm and Jaffe) that have done the most to study it. In any case it is beyond today's.