Knocking on Heaven’s Door: How Physics and Scientific Thinking Illuminate the Universe and the Modern World, Lisa Randall, HarperCollins, New York, 2011. $29.99 (442 pp.). ISBN 978-0-06-172372-8
Critical questions about the Big Bang or the “creation” of the universe bring together particle physicists, astrophysicists, theoretical physicists, and cosmologists in the search for answers that expand the domain of human understanding ever closer to the origin of time. The modern life, goals, and hopes of those scientists are described by theoretical physicist Lisa Randall in the remarkable book, Knocking on Heaven’s Door: How Physics and Scientific Thinking Illuminate the Universe and the Modern World. The book’s central character is the Large Hadron Collider at CERN, where a worldwide adventure unites 10 000 physicists from 85 countries. As I write this, the LHC has unveiled none of the exotic particles and phenomena that some theorists had dreamed of; but the hunt is not over, and progress has been extraordinary.
The versatile Randall, daughter of a modest family from Queens in New York City, can be found climbing rocks; attempting, with rage, the perfect ski turn in deep powder; and giving riveting talks to theorists, experimenters, and even nonscientists. She is one of the creative and incredibly dedicated theoretical physicists who gave the LHC experiments a precise goal: to discover traces of the additional dimensions of space that may explain the mystery of hierarchy—that is, why the masses of the particles we see are so small, when the symmetries of existing theories predict them to be a billion billion times heavier.
That Knocking on Heaven’s Door could be written in our time without being classified as metaphysics is a tribute to the extraordinary progress that science has made in the recent centuries. Says Randall, “Although there is much we don’t yet know about the evolution of the Universe, we have a spectacularly successful understanding of its evolution based on the . . . Big Bang theory.” That scientific understanding has developed through many challenging experiments that have delved deep into the atomic and subatomic worlds and into the cosmos. It was also guided by revolutionary new concepts: relativity and quantum mechanics, and now quantitative cosmology, spontaneous symmetry breaking, and string theory.
Those fields required new mathematics and new experimental techniques; they also called for new ways of thinking. Nature evolves not by force of a plan or a purpose, but by force of probability applied to the immensity of energy and time in the universe. Those reservoirs permit the most unlikely irreversible processes to begin—and once they are concluded, nothing will ever be the same. That perspective agrees amazingly with the one described by Nobel Prize–winning biologist Jacques Monod in his book, Chance and Necessity: An Essay on the Natural Philosophy of Modern Biology (Knopf, 1971).
Knocking on Heaven’s Door is deliciously written. Its description of CERN’s history is well documented and reflects with a wink several life experiences within the community of particle physicists. When reading it, you will travel through the 26.667-kilometer-long tunnel where the highest-energy protons ever prepared by humans circulate in a vacuum chamber. Colliding in detectors, those particles re-create conditions one step closer to the Big Bang than have been produced in any other accelerator. You will visit the experiments, but will also meet the people and discover their various accents and personalities. Besides being a top scientist, Randall is also a lover of people and a perceptive reader of their personalities.
Perhaps Randall’s most striking trait is courage, and it is fitting that she would, with great respect and understanding, address the burning underlying question: for a scientist, how about God, how about religion? She argues that scientists have not found any problem that demonstrably requires the intervention of a supernatural being animated with a purpose. They have, however, designed ways to establish a domain of truth based on experiments or observations that anyone can reproduce and that are related by theories that use mathematics agreed upon by all.
As a consequence of scientific endeavors, the internet allows the whole world to communicate and industry creates the most complicated machinery—for example the GPS in your car—based on past discoveries and parts built across the planet. And it all works! Yet what is the place of religion? Randall has the honesty and frankness to address the issue; she worked hard on documenting the debate, yet she never forgets that humans have souls.
