The question of what happened before the Big Bang long has frustrated cosmologists, both amateur and professional. Though Einstein's theory of general relativity does an excellent job of describing the universe almost back to its beginning, near the Big Bang matter becomes so dense that relativity breaks down, says Penn State physicist Abhay Ashtekar. "Beyond that point, we need to apply quantum tools that were not available to Einstein." Now Ashtekar and two of his post-doctoral researchers, Tomasz Pawlowski and Parmpreet Singh, have done just that. Using a theory called loop quantum gravity, they have developed a mathematical model that...