Examining the crossover from the hadronic to partonic phase in QCD.

A mechanism, consistent with color confinement, for the transition between perturbative and physical vacua during the gradual crossover from the hadronic to partonic phase is proposed. The essence of this mechanism is the appearance and growing up of a kind of grape-shape perturbative vacuum inside the physical one. A percolation model based on simple dynamics for parton delocalization is constructed to exhibit this mechanism. The crossover from hadronic matter to sQGP (strongly coupled quark-gluon plasma) as well as the transition from sQGP to weakly coupled quark-gluon plasma with increasing temperature is successfully described by using this model.

Two correlation patterns as indicators for underlying dynamics of complex systems.

Two spatial correlation patterns, fixed-to-arbitrary and neighboring bin correlation patterns, are suggested. It is demonstrated that these patterns present scale-independent and distinguishable measures for correlated and uncorrelated random multiplicative cascade processes. Their application to very high multiplicity events in relativistic heavy ion collisions is discussed.