The sPHENIX Experiment at RHIC seeks to understand the microscopic properties of the quark-gluon plasma (QGP). Two decades of work by the first generation RHIC experiments have firmly established the macroscopic properties of QGP, in particular its near-absence of internal friction (technically, the shear viscosity to entropy density ratio η/s, which can be thought of as a relativistic generalization of the engineer’s kinematic viscosity). The final-state flow patterns exhibit near-ideal hydrodynamic behavior on length scales ranging from ~1-10 femtometers. But we still do not have a good understanding of what is happening on the sub-femtometer scale, that is, how do (nominally?) asymptotically free quarks and gluons conspire to produce the “perfect liquid” behavior of QGP? sPHENIX seeks to answer this question by studying heavy flavor production and high transverse momentum jets and photons.