Advances made by physicists in understanding matter, space and time and by astronomers in understanding the universe as a whole have closely intertwined the question being asked about the universe at its two extremes - the very large and the very small. This report identifies 11 key questions that have a good chance of being answered by 2015. It urges that a new research strategy be created that brings to bear the techniques of both astronomy and sub-atomic physics in a cross-disciplinary way to address these questions. The report presents seven recommendations to facilitate the necessary research and development co-ordination. These recommendations identify key priorities for future scientific projects critical for realizing these scientific opportunities.