From Nobel prize-winner Roger Penrose, this groundbreaking book is for anyone "who is interested in the world, how it works, and how it got here" (New York Journal of Books). Penrose presents a new perspective on three of cosmology’s essential questions: What came before the Big Bang? What is the source of order in our universe? And what cosmic future awaits us? He shows how the expected fate of our ever-accelerating and expanding universe—heat death or ultimate entropy—can actually be reinterpreted as the conditions that will begin a new “Big Bang.” He details the basic principles beneath our universe, explaining various standard and non-standard cosmological models, the fundamental role of the cosmic microwave background, the paramount significance of black holes, and other basic building blocks of contemporary physics. Intellectually thrilling and widely accessible, Cycles of Time is a welcome new contribution to our understanding of the universe from one of our greatest mathematicians and thinkers.

Two world-renowned scientists present an audacious new vision of the cosmos that “steals the thunder from the Big Bang theory.” —Wall Street Journal The Big Bang theory—widely regarded as the leading explanation for the origin of the universe—posits that space and time sprang into being about 14 billion years ago in a hot, expanding fireball of nearly infinite density. Over the last three decades the theory has been repeatedly revised to address such issues as how galaxies and stars first formed and why the expansion of the universe is speeding up today. Furthermore, an explanation has yet to be found for what caused the Big Bang in the first place. In Endless Universe, Paul J. Steinhardt and Neil Turok, both distinguished theoretical physicists, present a bold new cosmology. Steinhardt and Turok “contend that what we think of as the moment of creation was simply part of an infinite cycle of titanic collisions between our universe and a parallel world” (Discover). They recount the remarkable developments in astronomy, particle physics, and superstring theory that form the basis for their groundbreaking “Cyclic Universe” theory. According to this theory, the Big Bang was not the beginning of time but the bridge to a past filled with endlessly repeating cycles of evolution, each accompanied by the creation of new matter and the formation of new galaxies, stars, and planets. Endless Universe provides answers to longstanding problems with the Big Bang model, while offering a provocative new view of both the past and the future of the cosmos. It is a “theory that could solve the cosmic mystery” (USA Today).

Landmark study discusses Einstein's theory, extends thermodynamics to special and general relativity, and also develops the applications of relativistic mechanics and thermodynamics to cosmological models.

These simple statements hold huge implications about how the universe must operate if it was truly infinite rather than finite, as is commonly thought. In one sense, this book, Universal Cycle Theory, may seem radical because it postulates that the universe operates in ways that are dramatically different from what we are taught. Yet, this new theory is conventional in the sense that it closely conforms to virtually all existing laws, equations, and observations. There are only two elements that make the Universal Cycle Theory radical cycles and infinity. Other than that, much of what you read in this book will seem familiar and conventional. Cycles are crucial because they are reflections of how matter behaves in an infinite universe: as vortices and waves. A vortex forms when matter rotates, producing circular cycles. A wave forms when colliding matter compresses and decompresses, producing linear cycles. Infinity is crucial because it explains the extent and structure of the universe. We assume that matter is infinitely divisible in the microscopic direction and infinitely integrable in the macroscopic direction. We assume that time was infinite in the past and will be infinite in the future. This concept of infinity is unique, having never been employed in a model of the universe before. It resolves many of the paradoxes and contradictions currently riddling physics and cosmology.

Nobel Prize–winning physicist Roger Penrose questions some of the most fashionable ideas in physics today, including string theory What can fashionable ideas, blind faith, or pure fantasy possibly have to do with the scientific quest to understand the universe? Surely, theoretical physicists are immune to mere trends, dogmatic beliefs, or flights of fancy? In fact, acclaimed physicist and bestselling author Roger Penrose argues that researchers working at the extreme frontiers of physics are just as susceptible to these forces as anyone else. In this provocative book, he argues that fashion, faith, and fantasy, while sometimes productive and even essential in physics, may be leading today's researchers astray in three of the field's most important areas—string theory, quantum mechanics, and cosmology. Arguing that string theory has veered away from physical reality by positing six extra hidden dimensions, Penrose cautions that the fashionable nature of a theory can cloud our judgment of its plausibility. In the case of quantum mechanics, its stunning success in explaining the atomic universe has led to an uncritical faith that it must also apply to reasonably massive objects, and Penrose responds by suggesting possible changes in quantum theory. Turning to cosmology, he argues that most of the current fantastical ideas about the origins of the universe cannot be true, but that an even wilder reality may lie behind them. Finally, Penrose describes how fashion, faith, and fantasy have ironically also shaped his own work, from twistor theory, a possible alternative to string theory that is beginning to acquire a fashionable status, to "conformal cyclic cosmology," an idea so fantastic that it could be called "conformal crazy cosmology." The result is an important critique of some of the most significant developments in physics today from one of its most eminent figures.

In the last twenty years, cosmology has unexpectedly emerged as one of the most exciting and dynamic fields of modern science. From astoundingly precise measurements of the cosmic microwave background to the ongoing mysteries of dark energy and dark matter, modern cosmology is unquestionably in the midst of its Golden Age. And yet, one of the most eminent mathematical physicists of our age, Roger Penrose is convinced that there is one fundamental problem that is consistently being overlooked: why did our universe begin in such a particular state of extremely low entropy? His Conformal Cyclic Cosmology (CCC) is an attempt to directly address that question. This extensive conversation between Howard Burton and Roger Penrose, co-recipient of the 2020 Nobel Prize in Physics and Emeritus Rouse Ball Professor of Mathematics at the Mathematical Institute at the University of Oxford, explores his motivation to come up with this theory in the first place and provides detailed insights into his groundbreaking research. This carefully-edited book includes an introduction, A Hidden Audience, and questions for discussion at the end of each chapter: I. Inadvertent Success - An inside look at a mysterious publishing phenomenon II. Considering Entropy - Minimum, maximum and both at the same time III. Mysteries and False Explanations - Dark issues and inflationary hyperbole IV. Conformal Geometry - Reinterpreting the end and the beginning V. CCC: The Basic Idea - Matching beginnings and ends, conformally VI. Light Cones - Photons vs. massive particles VII. Massive Headaches - And how we might make them disappear VIII. Necessary Conditions - Dark energy, dark matter and information loss in black holes IX. Cosmic Imprints? - Searching for evidence of past aeons X. Battling Onwards - Challenges of an irrepressibly independent thinker About Ideas Roadshow Conversations Series: This book is part of an expanding series of 100+ Ideas Roadshow conversations, each one presenting a wealth of candid insights from a leading expert through a focused yet informal setting to give non-specialists a uniquely accessible window into frontline research and scholarship that wouldn't otherwise be encountered through standard lectures and textbooks.

INSTANT NEW YORK TIMES BESTSELLER “Most appealing... technical accuracy and lightness of tone... Impeccable.”—Wall Street Journal “A porthole into another world.”—Scientific American “Brings science dissemination to a new level.”—Science The most trusted explainer of the most mind-boggling concepts pulls back the veil of mystery that has too long cloaked the most valuable building blocks of modern science. Sean Carroll, with his genius for making complex notions entertaining, presents in his uniquely lucid voice the fundamental ideas informing the modern physics of reality. Physics offers deep insights into the workings of the universe but those insights come in the form of equations that often look like gobbledygook. Sean Carroll shows that they are really like meaningful poems that can help us fly over sierras to discover a miraculous multidimensional landscape alive with radiant giants, warped space-time, and bewilderingly powerful forces. High school calculus is itself a centuries-old marvel as worthy of our gaze as the Mona Lisa. And it may come as a surprise the extent to which all our most cutting-edge ideas about black holes are built on the math calculus enables. No one else could so smoothly guide readers toward grasping the very equation Einstein used to describe his theory of general relativity. In the tradition of the legendary Richard Feynman lectures presented sixty years ago, this book is an inspiring, dazzling introduction to a way of seeing that will resonate across cultural and generational boundaries for many years to come.