The latest developments in physics have the potential to radically revise our understanding of the universe: its make-up its evolution & the fundamental forces that determine its operation. Knocking on Heavens Door is an exhilarating & accessible overview of these developments & a rousing defence of the role of science in our lives. There could be no better guide than Lisa Randall: the bestselling author of Warped Passages is an expert on both particle physics (the study of the smallest objects we know of) & cosmology (the study of the largest) & is one of the most highly regarded theoretical physicists in the world. In Knocking on Heavens Door she recounts the thrilling progress in our understanding of the universe from Galileo & Newton to Einstein & Feynman; she explores how we decide which scientific questions to study & how we go about answering them; & she examines the role of risk creativity uncertainty beauty & truth in scientific thinking. Throughout Lisa Randall explains with wit & clarity the latest ideas in physics & cosmology including the aims of the biggest & most expensive machine ever built: the Large Hadron Collider the enormous particle accelerator situated over a 100 metres below the French-Swiss border. More than 27 kilometres in circumference it has within it the hottest spot in the galaxy as well as the coldest & features the most powerful supercomputer system of all time. One of the most illuminating science books in years Knocking on Heavens Door makes clear the biggest scientific questions we face & reveals how answering them could ultimately tell us who we are & where we came from.