Many books look at either the nature of science as a method of knowledge creation or the state of current theories in particle physics and cosmology, Randall, a particle physicist, however, weaves narratives of both into a single book. While at first this may seem like pressing together two different topics, it works well to show science as a human process. The overall strength of Randall’s offering is in her lucid descriptions of the largest experimental machine ever built (the Large Hadron Collider in Switzerland, operated by CERN), the history of its construction and the many ways that physicists are using it and planning to use it to not only study their immediate scientific interests, but, in Randall’s words, to “ultimately tell us about who we are and where we came from.” Here, then, Randall shares her thoughts about the intersection between science and religion. While physicists are currently debating the recent claim from a lab associated with CERN that neutrinos were recorded exceeding the speed of light, Knocking on Heaven’s Door serves to remind that science is an evolving process, that all ideas in science are not set in stone but tentative to revision based on evidence.

Reviewed by Michael Barton