  Recent LHC data suggest that perturbative QCD provides a qualitatively
consistent picture of jet quenching. Constrained to RHIC pi0 suppression, zero
parameter WHDG energy loss predictions agree quantitatively with the charged
hadron v2 and D meson RAA measured at LHC and qualitatively with the charged
hadron RAA. On the other hand, RHIC-constrained LHC predictions from fully
strongly-coupled AdS/CFT qualitatively oversuppress D mesons compared to data;
light meson predictions are on less firm theoretical ground but also suggest
oversuppression. More detailed data from heavy, especially B, mesons will
continue to help clarify our picture of the physics of the quark-gluon plasma.
Since the approach of pQCD predictions to LHC data occurs at momenta >~ 15
GeV/c, a robust consistency check between pQCD and both RHIC and LHC data
requires RHIC jet measurements.
