Scope and limitations of a string theory dual description of the proton structure

Symmetric and antisymmetric structure functions from electromagnetic deep inelastic scattering of charged leptons off spin-1=2 hadrons are investigated in the framework of a top-down holographic dual description. We consider the Brower-Polchinski-Strassler-Tan Pomeron, type IIB superstring theory scattering ampli-tudes, and type IIB supergravity on AdS5 x S5. In all cases, the hard-wall prescription is used. Different kinematic regions of the Bjorken variable x, as well as the squared momentum of the virtual photon Q2, are studied in detail for FP2 and gP1 structure functions of the proton. Also, the virtual Compton scattering asymmetry of the proton AP1 is investigated. Comparison with data from several experimental collaborations is presented. In addition, the holographic Pomeron leads to predictions for the mentioned observables for very small x values. In particular, we present predictions for gP1 at Q2 around 10 GeV2, for data expected to be measured in a future electron-ion collider. Limitations of this holographic dual approach are discussed.

Automated summary

This study investigates the symmetric and antisymmetric structure functions in electromagnetic deep inelastic scattering using a holographic dual description. The Brower-Polchinski-Strassler-Tan Pomeron and type IIB superstring theory scattering amplitudes, as well as type IIB supergravity on AdS5 x S5, are considered. The study focuses on different kinematic regions of the Bjorken variable x and squared momentum of the virtual photon Q2 for proton structure functions FP2 and gP1. The analysis also includes the investigation of the virtual Compton scattering asymmetry AP1 of the proton. The predictions from the holographic Pomeron for small x values are compared with experimental data.