This award funds the research activities of Professor Matias Zaldarriaga at the Institute for Advanced Study, in Princeton, New Jersey. <br/><br/>Cosmology, the science devoted to understanding the history of our Universe as well as the physical laws that govern its evolution, is experiencing a revolution thanks to the healthy interplay between advances in fundamental physics and astrophysics and the availability of a vast amount of new data. In the next decades large surveys of the location of galaxies will play a central role as sources of new information. The work of Professor Zaldarriaga aims to improve our theoretical understanding of the physical processes responsible for the development of the structure that these surveys map. These surveys will also help to develop new modeling and analysis tools for such surveys and improve cosmological constraints derived from these observational studies. Research in this area thus advances the national interest by promoting the progress of one of the most fundamental areas of science: the discovery and characterization of the physical laws that describe the history of our Universe. The funded work is also expected to have significant broader impacts. Astronomy and cosmology are subjects of broad appeal to the public. Previous efforts by the PI to disseminate the research in a form accessible to non-scientists will be continued and expanded. These include periodic public lectures both for adults and in primary and middle schools, interviews in the media, including those targeted to Hispanic audiences, and a lecture series at a senior citizens center. The funded research will also contribute to the education of students and postdoctoral fellows. <br/><br/>More technically, the work of Professor Zaldarriaga will combine two state-of-the-art techniques: analytical effective field theory ideas that provide theoretical control with computational, and statistical techniques that confront theory with observations in an efficient and statistically principled way. The aim is to use these new techniques to harness previously inaccessible information about cosmological initial conditions and the non-linear physics that relates them to the observations, and thereby provide a unique and potentially transformative contribution to the field.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.