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.
"The triumph of Al-Khalili’s book is that it proves you can scrutinise the most complex parts of the universe without removing the colour, excitement and possibility from human life."鈥擷avier Greenwood, The Observer
"Al-Khalili is known as a brilliant explainer of science. . . . This is heady stuff, but Al-Khalili’s characterisation is one of the clearest I have read. . . . Delightfully, Al-Khalili also includes what he describes as a “bonus chapter” . . . that asks whether time travel is possible . . . He executes this skilfully, treading the line between having fun with this wild topic and staying true to himself as a serious physicist."鈥擩oshua Howgego, New Scientist
"It is clear that Al-Khalili is a first-rate communicator; that he “spent many a night on the edge of sleep . . . [inventing] fresh analogies and thought experiments”; that he cares deeply that readers should be as awed as he is. Many will better understand — and therefore enjoy — physics after reading his book."鈥擠ylan Neri, Financial Times
"Unless advanced physics is your thing (I'm betting not) then I'm probably right to say that everything you think you know about time is wrong. Until now, me too! But a book published this week - On Time by physicist Jim Al-Khalili – will make your head spin faster than the hands of a watch with a dodgy mainspring that's gone into overdrive."鈥擱ichard Madeley, Daily Express
"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."鈥擲imon Cocking, Irish Tech News
鈥淛im Al-Khalili鈥檚 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.鈥�鈥擝rian Greene, author of Until the End of Time
鈥淭ime 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.鈥�鈥擲ean Carroll, author of The Biggest Ideas in the Universe series
鈥淥ne of the best science writers, on one of the most fascinating topics in contemporary science: a must.鈥�鈥擟arlo Rovelli, author of The Order of Time
鈥淛im Al-Khalili has spent a lifetime thinking about time鈥攁nd 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.鈥�鈥擲teven Strogatz, author of Infinite Powers
鈥淚n 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.鈥�鈥擬artin Rees, author of On the Future: Prospects for Humanity
