Marko Đurić

At high energies, elastic hadronic cross sections, such as pp, pp, �±p, are domi- nated by vacuum exchange, which in leading order of the 1/Nc expansion has been identified as the BFKL Pomeron or its strong AdS dual the closed string Reggeized graviton (1). However the difference of particle anti-particle cross sections are given by a so-called Odderon, carrying C = -1 vacuum quantum numbers identified in weak coupling with odd numbers of exchanged gluons. Here we show that in the dual description the Odderon is the Reggeized Kalb-Ramond field (B�ν ) in the Neveu-Schwartz sector of closed string theory. To first order in strong coupling, the high energy contribution of Odderon is evaluated for N = 4 Super Yang-Mills by a generalization of the gravity dual analysis for Pomeron in Ref. (1). The con- sequence of confinement on the Odderon are estimated in the confining QCD-like AdS5 hardwall model of Polchinski and Strassler (2).

The AdS/CFT correspondence in principle gives a new approach to deep inelastic scattering as formulated by Polchinski and Strassler. Subsequently Brower, Polchinski, Strassler and Tan (BPST) computed the strong coupling kernel for the vacuum (or Pomeron) contribution to total cross sections. By identifying deep inelastic scattering with virtual photon total cross section, this allows a self consistent description at small-x where the dominant contribution is the vacuum exchange process. Here we formulate this contribution and compare it with HERA small-x DIS scattering data. We find that the BPST kernel along with a very simple local approximation to the proton and current “wave functions” gives a remarkably good fit not only at large Q 2 dominated by conformal symmetry but also extends to small Q 2, supplemented by a hard-wall cut-off of the AdS in the IR. We suggest that this is a useful phenomenological parametrization with implications for other diffractive processes, such as double diffractive Higgs production.

At high energies, elastic hadronic cross sections, such as pp, bar pp, π±p, are dominated by vacuum exchange, which in leading order of the 1/Nc expansion has been identified as the BFKL Pomeron or its strong AdS dual the closed string Reggeized graviton [1]. However the difference of particle anti-particle cross sections are given by a so-called Odderon, carrying C = -1 vacuum quantum numbers identified in weak coupling with odd numbers of exchanged gluons. Here we show that in the dual description the Odderon is the Reggeized Kalb-Ramond field (Bμν) in the Neveu-Schwartz sector of closed string theory. To first order in strong coupling, the high energy contribution of the Odderon is evaluated for Script N = 4 Super Yang-Mills by a generalization of the gravity dual analysis for the Pomeron in ref. [1]. The consequences of confinement on the Odderon are estimated in the confining QCD-like AdS5 hardwall model of Polchinski and Strassler [2].