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arXiv · hep-ph/0610115

Hadron Spectroscopy and Structure from AdS/CFT

Abstract

The AdS/CFT correspondence between conformal field theory and string states in an extended space-time has provided new insights into not only hadron spectra, but also their light-front wavefunctions. We show that there is an exact correspondence between the fifth-dimensional coordinate of anti-de Sitter space and a specific impact variable which measures the separation of the constituents within the hadron in ordinary space-time. This connection allows one to predict the form of the light-front wavefunctions of mesons and baryons, the fundamental entities which encode hadron properties and scattering amplitudes. A new relativistic Schrodinger light-front equation is found which reproduces the results obtained using the fifth-dimensional theory. Since they are complete and orthonormal, the AdS/CFT model wavefunctions can be used as an initial ansatz for a variational treatment or as a basis for the diagonalization of the light-front QCD Hamiltonian. A number of applications of light-front wavefunctions are also discussed.

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BibTeXRIS

Stanley J. Brodsky. 2006-10-10. Hadron Spectroscopy and Structure from AdS/CFT. https://doi.org/10.1140/epja%2Fi2006-10221-7

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