Relativistic hydrodynamic calculations are presented to describe the dynamicsof ultra-relativistic heavy-ion collisions. In contrast to the "standard picture" ofthe field, our calculations do not assume scaling symmetry, and in fact we findlarge scaling violations near the fragmentation regions. In our 1+1-dimensionalcalculations, we find that while the hydrodynamic evolution is very sensitive to theformation and thermalization time and to the models of the source terms, the effectsof changing the viscosity and the equation of state are small. Our 2+1-dimensionalcalculations show that transverse expansion is not important in the central rapidityregion. We also present a brief review of the proposed signatures of the formation ofquark-gluon plasma in high energy heavy-ion collisions, as examples of applicationsof hydrodynamics.
