Hadronic Spectra and LightFront Wavefunctions in Holographic QCD
Abstract
We show how the string amplitude {Phi}(z) defined on the fifth dimension in AdS{sub 5} space can be precisely mapped to the lightfront wavefunctions of hadrons in physical spacetime. We find an exact correspondence between the holographic variable z and an impact variable {zeta}, which represents the measure of transverse separation of the constituents within the hadrons. In addition, we derive effective four dimensional Schroedinger equations for the bound states of massless quarks and gluons which exactly reproduce the AdS/CFT results and give a realistic description of the lightquark meson and baryon spectrum as well as the form factors for spacelike Q{sup 2}. Only one parameter which sets the mass scale, {Lambda}{sub QCD}, is introduced.
 Authors:
 Publication Date:
 Research Org.:
 Stanford Linear Accelerator Center (SLAC)
 Sponsoring Org.:
 USDOE
 OSTI Identifier:
 877213
 Report Number(s):
 SLACPUB11716
hepph/0602252; TRN: US0601302
 DOE Contract Number:
 AC0276SF00515
 Resource Type:
 Technical Report
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; AMPLITUDES; BARYONS; BOUND STATE; DIMENSIONS; FORM FACTORS; GLUONS; HADRONS; MESONS; QUANTUM CHROMODYNAMICS; QUARKS; SCHROEDINGER EQUATION; SPACETIME; SPECTRA; PhenomenologyHEP,HEPPH, HEPTH
Citation Formats
Brodsky, Stanley J., and de Teramond, Guy F.. Hadronic Spectra and LightFront Wavefunctions in Holographic QCD. United States: N. p., 2006.
Web. doi:10.2172/877213.
Brodsky, Stanley J., & de Teramond, Guy F.. Hadronic Spectra and LightFront Wavefunctions in Holographic QCD. United States. doi:10.2172/877213.
Brodsky, Stanley J., and de Teramond, Guy F.. Fri .
"Hadronic Spectra and LightFront Wavefunctions in Holographic QCD". United States.
doi:10.2172/877213. https://www.osti.gov/servlets/purl/877213.
@article{osti_877213,
title = {Hadronic Spectra and LightFront Wavefunctions in Holographic QCD},
author = {Brodsky, Stanley J. and de Teramond, Guy F.},
abstractNote = {We show how the string amplitude {Phi}(z) defined on the fifth dimension in AdS{sub 5} space can be precisely mapped to the lightfront wavefunctions of hadrons in physical spacetime. We find an exact correspondence between the holographic variable z and an impact variable {zeta}, which represents the measure of transverse separation of the constituents within the hadrons. In addition, we derive effective four dimensional Schroedinger equations for the bound states of massless quarks and gluons which exactly reproduce the AdS/CFT results and give a realistic description of the lightquark meson and baryon spectrum as well as the form factors for spacelike Q{sup 2}. Only one parameter which sets the mass scale, {Lambda}{sub QCD}, is introduced.},
doi = {10.2172/877213},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Mar 03 00:00:00 EST 2006},
month = {Fri Mar 03 00:00:00 EST 2006}
}

A fundamental goal in QCD is to understand the nonperturbative structure of hadrons at the amplitude levelnot just the singleparticle flavor, momentum, and helicity distributions of the quark constituents, but also the multiquark, gluonic, and hiddencolor correlations intrinsic to hadronic and nuclear wavefunctions. A natural calculus for describing the boundstate structure of relativistic composite systems in quantum field theory is the lightfront Fock expansion which encodes the properties of a hadrons in terms of a set of frameindependent nparticle wavefunctions. Lightfront quantization in the doublytransverse lightcone gauge has a number of remarkable advantages, including explicit unitarity, a physical Fock expansion,more »

The structure of lightfront wavefunctions and constraints on hadronic form factors
We study the analytic structure of lightfront wave functions (LFWFs) and its consequences for hadron form factors using an explicitly Lorentzinvariant formulation of the front form. The normal to the light front is specified by a general null vector {omega}{sup {mu}}. The LFWFs with definite total angular momentum are eigenstates of a kinematic angular momentum operator and satisfy all Lorentz symmetries. They are analytic functions of the invariant mass squared of the constituents M{sub 0}{sup 2} = ({Sigma}k{sup {mu}}){sup 2} and the lightcone momentum fractions x{sub i} = k{sub i}{omega}/p{omega} multiplied by invariants constructed from the spin matrices, polarization vectors,more » 
Hadronic Spectra and LightFront Wave Functions in Holographic QCD
We show how the string amplitude {phi}(z) defined on the fifth dimension in AdS{sub 5} space can be precisely mapped to the lightfront wave functions of hadrons in physical spacetime. We find an exact correspondence between the holographic variable z and an impact variable {zeta}, which represents the measure of transverse separation of the constituents within the hadrons. In addition, we derive effective four dimensional Schroedinger equations for the bound states of massless quarks and gluons which exactly reproduce the antide Sitter conformal field theory results and give a realistic description of the lightquark meson and baryon spectrum as wellmore » 
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