Fluctuation probes of quark deconfinement

The size of the average fluctuations of net baryon number and electric char ge in a finite volume of hadronic matter differs widely between the confine d and deconfined phases. These differences may be exploited as indicators o f the formation of a quark-gluon plasma in relativistic heavy-ion collision s, because fluctuations created in the initial state survive until freeze-o ut due to the rapid expansion of the hot fireball.