Dark matter and dark energy are the dominant components of the Universe. Their ultimate nature, however, remains mysterious, especially so of the dark energy. Ambitious ground and space-based missions investigating different aspects of the “Dark Universe” constitute a national and international investment measured in billions of dollars. The discovery potential of almost all of these missions relies crucially on theoretical modeling of the large-scale structure of the Universe. As observational error estimates for various cosmological statistics edge towards the one percent level, it is imperative that simulation capability be developed to a point that the entire enterprise is no longer theory-limited.

This project is a simulation framework powerful enough to discover signatures of new physics from next- generation cosmological observations. Relevant questions include: (1) Beyond the cosmological constant, what are the detectable signatures of a dynamical equation of state for dark energy? (2) How does modification of general relativity alter the nonlinear regime of structure formation? As for dark matter and related questions: (1) What are the effects of plausible dark matter candidates on the mass distribution? (2) What are the constraints on the neutrino sector from cosmological observations? In addition, the results of the simulations will be very useful for a range of astrophysical investigations, primarily in the areas of galaxy formation and the formation and evolution of galaxy groups and clusters. This is possible because the next generation, 10-petaflops IBM Blue Gene system will provide, at last, the computational power to resolve galaxy-scale mass concentrations in a simulated volume as large as state-of-the-art sky surveys. Researchers will generate numerically a mock galaxy catalog that will allow the determination of the effects of new physics on major cosmological observables.