While we have come a long way toward deciphering the laws of the universe, many physicists still regard time to be one of the greatest unsolved mysteries. On Time provides answers to the questions about time that philosophers and scientists have been asking for millennia, such as whether it has a beginning and an end, why it only points toward the future and not the past, whether it can be stretched and squeezed or even reversed, and whether it is even real.
In this mind-altering book, Jim Al-Khalili tackles the enduring problems of time head-on, carefully examining them across the three central pillars of physics鈥攓uantum mechanics, general relativity, and thermodynamics. He shows how, in each domain, time can be understood differently: as a coordinate or label, as an inseparable dimension of space-time, or as a direction or 鈥渁rrow.鈥� He explains why it can be difficult to reconcile these different perspectives and describes how theorists at the frontiers of physics are attempting to do just that. Al-Khalili makes the persuasive case that time is real, not illusory, and that a master arrow of time is not merely a trick of our senses but is rather a fundamental feature of reality that was baked into the structure of our universe from the very beginning.
Sharing fresh insights into some of the most complex and profound questions in science, On Time will forever change the way you think about the passage of time and your place within it.
Jim Al-Khalili is Distinguished Professor Emeritus of Physics at the University of Surrey and one of Britain’s leading science communicators. He has written numerous books that have been translated into twenty-six languages, among them The Joy of Science and The World According to Physics (both 快色直播). A fellow of the Royal Society, he is a regular presenter of TV science documentaries and is best-known in the UK for his long-running BBC Radio program, The Life Scientific.
“Jim Al-Khalili’s On Time is a wonderful exploration of one of the most familiar and mysterious aspects of existence: time itself. Clear, concise, and compelling, the book illuminates some of the deepest insights about time discovered by some of our greatest thinkers, which have rewritten the very rules of reality.”—Brian Greene, author of Until the End of Time
“Time is a crucial aspect of our existence, yet its nature continues to puzzle us. Jim Al-Khalili fearlessly tackles the big questions here: Is time real? Why does it have a direction? How does it fit into the fundamental laws of physics? You will come away from this engaging book with a much deeper understanding of what we know and what we have yet to learn about something so familiar and yet so perplexing.”—Sean Carroll, author of The Biggest Ideas in the Universe series
“One of the best science writers, on one of the most fascinating topics in contemporary science: a must.”—Carlo Rovelli, author of The Order of Time
“Jim Al-Khalili has spent a lifetime thinking about time—and in this warm, witty book, he lets us watch him think. Roaming freely among physics, philosophy, and lived experience, he explores competing ideas with fairness and humor. On Time is a rare thing: a deep scientific book with an open heart.”—Steven Strogatz, author of Infinite Powers
“In this fascinating and insightful book, celebrated communicator and distinguished physicist Jim Al-Khalili brilliantly deploys his talents on the nature of time, a challenging topic that has perplexed philosophers for centuries and poses novel mysteries for modern physicists.”—Martin Rees, author of On the Future: Prospects for Humanity
