AdS/QCD, LIightFront Holography, and the Nonperturbative Running Coupling
Abstract
The combination of Antide Sitter space (AdS) methods with lightfront (LF) holography provides a remarkably accurate first approximation for the spectra and wavefunctions of meson and baryon lightquark bound states. The resulting boundstate Hamiltonian equation of motion in QCD leads to relativistic lightfront wave equations in terms of an invariant impact variable {zeta} which measures the separation of the quark and gluonic constituents within the hadron at equal lightfront time. These equations of motion in physical spacetime are equivalent to the equations of motion which describe the propagation of spinJ modes in antide Sitter (AdS) space. The eigenvalues give the hadronic spectrum, and the eigenmodes represent the probability distributions of the hadronic constituents at a given scale. A positivesign confining dilaton background modifying AdS space gives a very good account of meson and baryon spectroscopy and form factors. The lightfront holographic mapping of this model also leads to a nonperturbative effective coupling {alpha}{sub s}{sup Ads} (Q{sup 2}) which agrees with the effective charge defined by the Bjorken sum rule and lattice simulations. It displays a transition from perturbative to nonperturbative conformal regimes at a momentum scale {approx} 1 GeV. The resulting {beta}function appears to capture the essential characteristics of themore »
 Authors:
 Publication Date:
 Research Org.:
 SLAC National Accelerator Lab., Menlo Park, CA (United States)
 Sponsoring Org.:
 USDOE
 OSTI Identifier:
 979043
 Report Number(s):
 SLACPUB13998
arXiv:1002.4660; TRN: US1003079
 DOE Contract Number:
 AC0276SF00515
 Resource Type:
 Conference
 Resource Relation:
 Conference: Invited talk at International Workshop on Strong Coupling Gauge Theories in LHC Era: SCGT 09, Nagoya, Japan, 811 Dec 2009
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; APPROXIMATIONS; BARYON SPECTROSCOPY; BARYONS; BOUND STATE; DUALITY; EFFECTIVE CHARGE; EIGENVALUES; EQUATIONS OF MOTION; FORM FACTORS; HADRONS; HAMILTONIANS; HOLOGRAPHY; MESONS; PROBABILITY; QUANTUM CHROMODYNAMICS; QUARKS; SPACETIME; SPECTRA; SUM RULES; WAVE EQUATIONS; PhenomenologyHEP,HEPPH, HEPTH
Citation Formats
Brodsky, Stanley J., /SLAC, de Teramond, Guy, /Costa Rica U., Deur, Alexandre, and /Jefferson Lab. AdS/QCD, LIightFront Holography, and the Nonperturbative Running Coupling. United States: N. p., 2010.
Web.
Brodsky, Stanley J., /SLAC, de Teramond, Guy, /Costa Rica U., Deur, Alexandre, & /Jefferson Lab. AdS/QCD, LIightFront Holography, and the Nonperturbative Running Coupling. United States.
Brodsky, Stanley J., /SLAC, de Teramond, Guy, /Costa Rica U., Deur, Alexandre, and /Jefferson Lab. 2010.
"AdS/QCD, LIightFront Holography, and the Nonperturbative Running Coupling". United States.
doi:. https://www.osti.gov/servlets/purl/979043.
@article{osti_979043,
title = {AdS/QCD, LIightFront Holography, and the Nonperturbative Running Coupling},
author = {Brodsky, Stanley J. and /SLAC and de Teramond, Guy and /Costa Rica U. and Deur, Alexandre and /Jefferson Lab},
abstractNote = {The combination of Antide Sitter space (AdS) methods with lightfront (LF) holography provides a remarkably accurate first approximation for the spectra and wavefunctions of meson and baryon lightquark bound states. The resulting boundstate Hamiltonian equation of motion in QCD leads to relativistic lightfront wave equations in terms of an invariant impact variable {zeta} which measures the separation of the quark and gluonic constituents within the hadron at equal lightfront time. These equations of motion in physical spacetime are equivalent to the equations of motion which describe the propagation of spinJ modes in antide Sitter (AdS) space. The eigenvalues give the hadronic spectrum, and the eigenmodes represent the probability distributions of the hadronic constituents at a given scale. A positivesign confining dilaton background modifying AdS space gives a very good account of meson and baryon spectroscopy and form factors. The lightfront holographic mapping of this model also leads to a nonperturbative effective coupling {alpha}{sub s}{sup Ads} (Q{sup 2}) which agrees with the effective charge defined by the Bjorken sum rule and lattice simulations. It displays a transition from perturbative to nonperturbative conformal regimes at a momentum scale {approx} 1 GeV. The resulting {beta}function appears to capture the essential characteristics of the full {beta}function of QCD, thus giving further support to the application of the gauge/gravity duality to the confining dynamics of strongly coupled QCD.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2010,
month = 4
}

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