David Higdon, Los Alamos National Laboratory

IAMCS Workshop in Large-Scale Inverse Problems and Uncertainty Quantification

February 24-25, 2011

Stephen W. Hawking Auditorium

George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy

Texas A&M University

College Station, Texas

Emulating the Nonlinear Matter Power Spectrum for the Universe

Very accurate simulations of the large scale structure of the universe are required to estimate and constrain cosmological parameters governing a cold dark matter model of the universe. This application makes use of a suite of nearly 1000 N-body simulations at different force and mass resolutions to explore 38 different cosmologies spanning a 5-dimensional parameter space. The statistical challenge of this application is combining information from these computational simulations which are run at different resolutions to build an emulator which predicts model output at untried parameter settings. With this emulator, we can then use physical observations to estimate/constrain cosmological parameters governing the model.