Conformal symmetry and light flavor baryon spectra

Abstract

The degeneracy among parity pairs systematically observed in the N and Delta spectra is interpreted to hint on a possible conformal symmetry realization in the light flavor baryon sector in line with AdS_5/CFT_4. The case is made by showing that all the observed N and Delta resonances with masses below 2500 MeV distribute fairly well each over the first levels of a unitary representation of the conformal group, a representation that covers the spectrum of a quark-diquark system, placed directly on the AdS_5 cone, conformally compactified to R^1*S^3. The free geodesic motion on the S^3 manifold is described by means of the scalar conformal equation there, which is of the Klein-Gordon type. The equation is then gauged by the "curved" Coulomb potential that has the form of a cotangent function. Conformal symmetry is not exact, this because the gauge potential slightly modifies the conformal centrifugal barrier of the free geodesic motion. Thanks to this, the degeneracy between P11-S11 pairs from same level is relaxed, while the remaining states belonging to same level remain practically degenerate. The model describes the correct mass ordering in the P11-S11 pairs through the nucleon spectrum as a combined effect of the above conformal symmetry breaking, on the one side, and a parity change of the diquark from a scalar at low masses, to a pseudoscalar at higher masses, on the other. The quality of the wave functions is illustrated by calculations of realistic mean-square charge radii and electric charge form-factors on the examples of the proton, and the protonic P11(1440), and S11(1535) resonances. The scheme also allows for a prediction of the dressing function of an effective instantaneous gluon propagator from the Fourier transform of the gauge potential. We find a dressing function that is finite in the infrared and tends to zero at infinity.

arXiv commentLatex, 5 figures, 2 tables; Paper upgraded in accord with the published version. Discussion on the meson sector included

References in corpus (48)

• Big Bang Nucleosynthesis (in "The Review of Particle Properties" 2004)
• A Stress Tensor for Anti-de Sitter Gravity
• Wilson loops in large N field theories
• Diquarks and Exotic Spectroscopy
• Exotica
• Gluon and ghost propagators in the Landau gauge: Deriving lattice results from Schwinger-Dyson equations
• Hadronic Spectra and Light-Front Wavefunctions in Holographic QCD
• Hadronic Spectrum of a Holographic Dual of QCD
• The Infrared Behavior of Gluon and Ghost Propagators in Landau Gauge QCD
• Baryon spectroscopy
• Vacuum interpolation in supergravity via super p-branes
• Detailed Analysis of the Three Quark Potential in SU(3) Lattice QCD
• Electromagnetic Meson Production in the Nucleon Resonance Region
• Effective Field Theory Lagrangians for Baryons with Two and Three Heavy Quarks
• An interacting quark-diquark model of baryons
• On the spectrum of nonrelativistic AdS/CFT
• Conformal Maxwell theory as a singleton field theory on AdS_5, IIB three-branes and duality
• Spectrum of Large N Gauge Theory from Supergravity
• The Trigonometric Rosen-Morse Potential in the Supersymmetric Quantum Mechanics and its Exact Solutions
• Light-Front Holography and Gauge/Gravity Duality: The Light Meson and Baryon Spectra
• On exact solutions and singularities in string theory
• Light meson spectrum and classical symmetries of QCD
• Parity doubling in particle physics
• Static strings in Randall-Sundrum scenarios and the quark anti-quark potential
• The Gluon Propagator without lattice Gribov copies on a finer lattice
• Partial dynamical symmetry in quantum Hamiltonians with higher-order terms
• Electromagnetic nucleon form factors in instant and point form
• Romanovski polynomials in selected physics problems
• Curved branes from string dualities
• On the Parity Degeneracy of Baryons
• Brane-induced Skyrmion on S^3: baryonic matter in holographic QCD
• Holographic Nuclei
• Trigonometric quark confinement potential of QCD traits
• Sphalerons and Conformally Compactified Minkowski Spacetime
• A Holographic QCD and Excited Baryons from String Theory
• Baryons in O(4) and Vibron Model
• From Marginal Deformations to Confinement
• Classifying Reported and "Missing" Resonances According to Their P and C Properties
• Holographic Nuclei : Supersymmetric Examples
• Conformal boundary and geodesics for $Ad{S}_5\times S^5$ and the plane wave: Their approach in the Penrose limit
• Degeneracy Symmetry Of Baryon Spectra
• Delta resonances, quark models, chiral symmetry and AdS/QCD
• Multi-quark potential from AdS/QCD
• Infrared Propagators in MAG and Feynman gauge on the lattice
• Structure of the Nucleon and Roper Resonance with Diquark Correlations
• Momentum space trigonometric Rosen-Morse potential
• "McKay's E7 observation on the Baby Monster" and "McKay's E6 observation on the largest Fischer group"
• Baryons from quarks in curved space and deconfinement

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• Light-Front Holographic QCD and Emerging Confinement
• Excited Baryons in Holographic QCD
• Hadronic Form Factor Models and Spectroscopy Within the Gauge/Gravity Correspondence
• Applications of AdS/QCD and Light-Front Holography to Baryon Physics
• Modelling duality between bound and resonant meson spectra by means of free quantum motions on the de Sitter space time dS4
• On the exact solubility in momentum space of the trigonometric Rosen-Morse potential
• Light-Front Quantization and AdS/QCD: An Overview
• Light-Front Holography, Light-Front Wavefunctions, and Novel QCD Phenomena
• Symmetry and degeneracy of the curved Coulomb potential on the S3 ball
• The Higgs oscillator on the hyperbolic plane and Light-Front Holography
• Potentials on the conformally compactified Minkowski spacetime and their application to quark deconfinement
• Relativistic oscillator model with spin for nucleon resonances