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Fields and quanta



In QCD a bound state of quarks via the strong nuclear force.

Binding two quarks: meson

Binding three quarks: baryon.


Computation via lattice QCD

Comparison of light hadron masses as seen in accelertator experiment and in lattice QCD-computer simulation (from Fodor-Hoelbling 12)

Conceptualization and computation in AdS/QCD

In the Witten-Sakai-Sugimoto model for strongly coupled QCD via an intersecting D-brane model, the hadrons in QCD correspond to string-theoretic-phenomena in an ambient bulk field theory on an approximately anti de Sitter spacetime:

  1. the mesons (bound states of 2 quarks) correspond to open strings in the bulk, whose two endpoints on the asymptotic boundary correspond to the two quarks;

  2. baryons (bound states of N cN_c quarks) appear in two different but equivalent (Sugimoto 16, 15.4.1) guises:

    1. as wrapped D4-branes with N cN_c open strings connecting them to the D8-brane

      (Witten 98b, Gross-Ooguri 98)

    2. as skyrmions

      (Sakai-Sugimoto 04, section 5.2, Sakai-Sugimoto 05, section 3.3, see Bartolini 17).

For review see Sugimoto 16, also Rebhan 14, around (18).

graphics grabbed from Sugimoto 16

This produces baryon mass spectra with moderate quantitative agreement with experiment (HSSY 07):

graphics grabbed from Sugimoto 16



See also:


Observations at LHC:

  • Maria Vasileiou on behalf of the ALICE Collaboration, Measurement of the Hadronic Resonance Production with ALICE at the CERN LHC, Universe 2019, 5(1), 6 (doi:10.3390/universe5010006)

In lattice QCD

Computation of the mass of hadrons using lattice QCD (see also confinement and mass gap problem) is discussed in

  • S. Durr, Z. Fodor, J. Frison, C. Hoelbling, R. Hoffmann, S.D. Katz, S. Krieg, T. Kurth, L. Lellouch, T. Lippert, K.K. Szabo, G. Vulvert,

    Ab-initio Determination of Light Hadron Masses,

    Science 322:1224-1227,2008 (arXiv:0906.3599)

    conclusion on p. 4:

our study strongly suggests that QCD is the theory of the strong interaction, at low energies as well

  • Zoltan Fodor, Christian Hoelbling, Light Hadron Masses from Lattice QCD, Rev. Mod. Phys. 84, 449, (arXiv:1203.4789)

  • S. Aoki et. al. Review of lattice results concerning low-energy particle physics (arXiv:1607.00299)

In Witten-Sakai-Sugimoto model for AdS-QCD


Last revised on February 13, 2020 at 07:48:16. See the history of this page for a list of all contributions to it.