The Defense Advanced Research Projects Agency (DARPA) is soliciting innovative proposals in the general area of extreme-scale hydrodynamics, including, but not limited to, high amplitude wave propagat... The Defense Advanced Research Projects Agency (DARPA) is soliciting innovative proposals in the general area of extreme-scale hydrodynamics, including, but not limited to, high amplitude wave propagation, very high Reynolds number flows, and abrupt phase changes. Proposed research should investigate innovative theoretical and computational modeling approaches relying on first principles-based closures of the governing laws of fluid motion under such conditions.