A perfect fluid is a liquid that exhibits nearly zero viscosity. However, there is a lower limit to what is physically possible defined by a ratio of viscosity against entropy - ħ/4π where ħ is the Plank constant. Despite this theoretical limit, nearly no fluids exhibited behaviors anywhere close except for quark-gluon plasmas. Unfortunately, until recently, scientists were struggling with how to measure the fleetingly short-lived, primordial soup substance. In order to study it, researchers learned they could measure particle jets of known energy that are ejected from the quark-gluon plasma. After creating mathematical models for the plasma based on relativistic hydrodynamics, the scientists were able to study how the jets passed through the plasma in order to infer information about the plasma itself. The discovery of the "perfect fluids" was made nearly 10 years ago, but the existing data from the RHIC and LHC against the new models have allowed researchers to expand into creating quark-gluon plasmas from unexpected sources. According to physicists at the University of Colorado, "The idea that collisions of small particles with larger nuclei might create minute droplets of primordial quark-gluon plasma has guided a series of experiments to test this idea and alternative explanations, and stimulated a rich debate about the implications of these findings .... These experiments are revealing the key elements required for creating quark-gluon plasma and could also offer insight into the initial state characteristics of the colliding particles."