  A generic jet-energy loss model that is coupled to state-of-the-art
hydrodynamic fields and interpolates between a wide class of running coupling
pQCD-based and AdS/CFT-inspired models is compared to recent data on the
azimuthal and transverse momentum dependence of high-pT pion nuclear
modification factors and high-pT elliptic flow measured at RHIC and LHC. We
find that RHIC data are surprisingly consistent with various scenarios
considered. However, extrapolations to LHC energies favor running coupling
pQCD-based models of jet-energy loss. While conformal holographic models are
shown to be inconsistent with data, recent non-conformal generalizations of AdS
holography may provide an alternative description.
