Towards the Realistic Gluodynamics String. Perturbative Gluons' Contribution to the String Effective Action

Abstract

Perturbation theory in the nonperturbative QCD vacuum and the non-Abelian Stokes theorem, representing a Wilson loop in the SU(2) gluodynamics as an integral over all the orientations in colour space, are applied to derivation of the correction to the background-induced string effective action. This correction is due to accounting in the lowest order of perturbation theory for the interaction of perturbative gluons with the string world sheet. It occurs that this interaction affects only the coupling constant of the rigidity term, while its contribution to the string tension of the Nambu-Goto term vanishes. The obtained correction to the rigid string coupling constant multiplicatively depends on the spin of the representation of the Wilson loop under consideration, the QCD coupling constant and a certain path integral, which includes the background Wilson average.