ADS/CFT and QCD
Abstract
The AdS/CFT correspondence between string theory in AdS space and conformal .eld theories in physical spacetime leads to an analytic, semiclassical model for stronglycoupled QCD which has scale invariance and dimensional counting at short distances and color confinement at large distances. Although QCD is not conformally invariant, one can nevertheless use the mathematical representation of the conformal group in fivedimensional antide Sitter space to construct a first approximation to the theory. The AdS/CFT correspondence also provides insights into the inherently nonperturbative aspects of QCD, such as the orbital and radial spectra of hadrons and the form of hadronic wavefunctions. In particular, we show that there is an exact correspondence between the fifthdimensional coordinate of AdS space z and a specific impact variable {zeta} which measures the separation of the quark and gluonic constituents within the hadron in ordinary spacetime. This connection allows one to compute the analytic form of the frameindependent lightfront wavefunctions, the fundamental entities which encode hadron properties and allow the computation of decay constants, form factors, and other exclusive scattering amplitudes. New relativistic lightfront equations in ordinary spacetime are found which reproduce the results obtained using the 5dimensional theory. The effective lightfront equations possess remarkable algebraic structuresmore »
 Authors:
 Publication Date:
 Research Org.:
 Stanford Linear Accelerator Center (SLAC)
 Sponsoring Org.:
 USDOE
 OSTI Identifier:
 899840
 Report Number(s):
 SLACPUB12361
TRN: US0702104
 DOE Contract Number:
 AC0276SF00515
 Resource Type:
 Conference
 Resource Relation:
 Conference: Invited talk at 2006 International Workshop on the Origin of Mass and Strong Coupling Gauge Theories (SCGT 06), Nagoya, Japan, 2124 Nov 2006
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; APPROXIMATIONS; COLOR; CONFINEMENT; CONFORMAL GROUPS; DECAY; FORM FACTORS; HADRONS; ORIGIN; QUANTUM CHROMODYNAMICS; QUARKS; SCALE INVARIANCE; SCATTERING AMPLITUDES; SPACETIME; SPECTRA; TheoryHEP,HEPPH, HEPTH
Citation Formats
Brodsky, Stanley J., /SLAC, de Teramond, Guy F., and /Costa Rica U. /SLAC. ADS/CFT and QCD. United States: N. p., 2007.
Web.
Brodsky, Stanley J., /SLAC, de Teramond, Guy F., & /Costa Rica U. /SLAC. ADS/CFT and QCD. United States.
Brodsky, Stanley J., /SLAC, de Teramond, Guy F., and /Costa Rica U. /SLAC. Wed .
"ADS/CFT and QCD". United States.
doi:. https://www.osti.gov/servlets/purl/899840.
@article{osti_899840,
title = {ADS/CFT and QCD},
author = {Brodsky, Stanley J. and /SLAC and de Teramond, Guy F. and /Costa Rica U. /SLAC},
abstractNote = {The AdS/CFT correspondence between string theory in AdS space and conformal .eld theories in physical spacetime leads to an analytic, semiclassical model for stronglycoupled QCD which has scale invariance and dimensional counting at short distances and color confinement at large distances. Although QCD is not conformally invariant, one can nevertheless use the mathematical representation of the conformal group in fivedimensional antide Sitter space to construct a first approximation to the theory. The AdS/CFT correspondence also provides insights into the inherently nonperturbative aspects of QCD, such as the orbital and radial spectra of hadrons and the form of hadronic wavefunctions. In particular, we show that there is an exact correspondence between the fifthdimensional coordinate of AdS space z and a specific impact variable {zeta} which measures the separation of the quark and gluonic constituents within the hadron in ordinary spacetime. This connection allows one to compute the analytic form of the frameindependent lightfront wavefunctions, the fundamental entities which encode hadron properties and allow the computation of decay constants, form factors, and other exclusive scattering amplitudes. New relativistic lightfront equations in ordinary spacetime are found which reproduce the results obtained using the 5dimensional theory. The effective lightfront equations possess remarkable algebraic structures and integrability properties. Since they are complete and orthonormal, the AdS/CFT model wavefunctions can also be used as a basis for the diagonalization of the full lightfront QCD Hamiltonian, thus systematically improving the AdS/CFT approximation.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Wed Feb 21 00:00:00 EST 2007},
month = {Wed Feb 21 00:00:00 EST 2007}
}

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