Tachyonic AdS/QCD, Determining the Strong Running Coupling and β-function in both UV and IR Regions of AdS Space

Abstract

In this paper we investigate the QCD running coupling α AdS s (Q 2 ) and the associated β-function β(Q 2 ) in the spirit of tachyonic AdS/QCD. We distort the AdS5 conformal symmetry using color dielectric function G(φ(z)) associated with free tachyons. Results obtained in this region are expected to present characteristics similar to the perturbative QCD. We further study the distortion of the conformal symmetry with condensed tachyon color dielectric function G(η(z)) which leads to color confinement in the IR region similar to low energy nonperturbative QCD. Results obtained in this region are compared with AdS/QCD with positive dilaton profile, e κ 2 z 2 . The color dielectric function is carefully defined to generate the needed characteristics in both regions with dependence only on fifth dimensional coordinate z.