But ask what it means, and the result will be a brawl. For a century, most physicists have followed Niels Bohr's Copenhagen interpretation and dismissed questions about the reality underlying quantum physics as meaningless. A mishmash of solipsism and poor reasoning, Copenhagen endured, as Bohr's students vigorously protected his legacy, and the physics community favored practical experiments over philosophical arguments. As a result, questioning the status quo long meant professional ruin. And yet, from the 1920s to today, physicists like John Bell, David Bohm, and Hugh Everett persisted in seeking the true meaning of quantum mechanics. What Is Real? is the gripping story of this battle of ideas and of the courageous scientists who dared to stand up for truth.

    For more than two centuries, our understanding of the laws of nature expanded rapidly. But today, despite our best efforts, we know nothing more about these laws than we knew in the 1970s. Why is physics suddenly in trouble? And what can we do about it?One of the major problems, according to Smolin, is string theory: an ambitious attempt to formulate a “theory of everything” that explains all the particles and forces of nature and how the universe came to be. With its exotic new particles and parallel universes, string theory has captured the public’s imagination and seduced many physicists.But as Smolin reveals, there’s a deep flaw in the theory: no part of it has been tested, and no one knows how to test it. In fact, the theory appears to come in an infinite number of versions, meaning that no experiment will ever be able to prove it false. As a scientific theory, it fails. And because it has soaked up the lion’s share of funding, attracted some of the best minds, and effectively penalized young physicists for pursuing other avenues, it is dragging the rest of physics down with it.With clarity, passion, and authority, Smolin charts the rise and fall of string theory and takes a fascinating look at what will replace it. A group of young theorists has begun to develop exciting ideas that, unlike string theory, are testable. Smolin not only tells us who and what to watch for in the coming years, he offers novel solutions for seeking out and nurturing the best new talent—giving us a chance, at long last, of finding the next Einstein.

    Most scientists didn't recognize the import of Hawking's claims, but Leonard Susskind and Gerard t'Hooft realized the threat, and responded with a counterattack that changed the course of physics.The Black Hole War is the thrilling story of their united effort to reconcile Hawking's revolutionary theories of black holes with their own sense of reality -- effort that would eventually result in Hawking admitting he was wrong, paying up, and Susskind and t'Hooft realizing that our world is a hologram projected from the outer boundaries of space.A brilliant book about modern physics, quantum mechanics, the fate of stars and the deep mysteries of black holes, Leonard Susskind's account of the Black Hole War is mind-bending and exhilarating reading.

    In Dyson's view, science and religion are two windows through which we can look out at the world around us. The book is a revised version of a series of the Gifford Lectures under the title "In Praise of Diversity" given at Aberdeen, Scotland. They allowed Dyson the license to express everything in the universe, which he divided into two parts in polished prose: focusing on the diversity of the natural world as the first, and the diversity of human reactions as the second half.Chapter 1 is a brief explanation of Dyson's attitudes toward religion and science. Chapter 2 is a one–hour tour of the universe that emphasizes the diversity of viewpoints from which the universe can be encountered as well as the diversity of objects which it contains. Chapter 3 is concerned with the history of science and describes two contrasting styles in science: one welcoming diversity and the other deploring it. He uses the cities of Manchester and Athens as symbols of these two ways of approaching science. Chapter 4, concerned with the origin of life, describes the ideas of six illustrious scientists who have struggled to understand the nature of life from various points of view. Chapter 5 continues the discussion of the nature and evolution of life. The question of why life characteristically tends toward extremes of diversity remains central in all attempts to understand life's place in the universe. Chapter 6 is an exercise in eschatology, trying to define possible futures for life and for the universe, from here to infinity. In this chapter, Dyson crosses the border between science and science fiction and he frames his speculations in a slightly theological context.

    He looks at the difficult dialogue between science and religion; the conflict between our human desire for permanence and the impermanence of nature; the possibility that our universe is simply an accident; the manner in which modern technology has separated us from direct experience of the world; and our resistance to the view that our bodies and minds can be explained by scientific logic and laws. And behind all of these considerations is the suggestion—at once haunting and exhilarating—that what we see and understand of the world is only a tiny piece of the extraordinary, perhaps unfathomable whole.

    Our Big Bang, our distant future, parallel worlds, the sub-atomic and intergalactic - none of them are what they seem. But there is a way to understand this immense strangeness - mathematics. Seeking an answer to the fundamental puzzle of why our universe seems so mathematical, Tegmark proposes a radical idea: that our physical world not only is described by mathematics, but that it is mathematics. This may offer answers to our deepest questions: How large is reality? What is everything made of? Why is our universe the way it is?Table of ContentsPreface 1 What Is Reality? Not What It Seems • What’s the Ultimate Question? • The Journey Begins Part One: Zooming Out 2 Our Place in Space Cosmic Questions • How Big Is Space? • The Size of Earth • Distance to the Moon • Distance to the Sun and the Planets • Distance to the Stars • Distance to the Galaxies • What Is Space? 3 Our Place in TimeWhere Did Our Solar System Come From? • Where Did theGalaxies Come From? • Where Did the Mysterious MicrowavesCome From? • Where Did the Atoms Come From? 4 Our Universe by NumbersWanted: Precision Cosmology • Precision Microwave-Background Fluctuations • Precision Galaxy Clustering • The Ultimate Map of Our Universe • Where Did Our Big Bang Come From? 5 Our Cosmic Origins What’s Wrong with Our Big Bang? • How Inflation Works • The Gift That Keeps on Giving • Eternal Inflation 6 Welcome to the Multiverse The Level I Multiverse • The Level II Multiverse • Multiverse Halftime Roundup Part Two: Zooming In 7 Cosmic Legos Atomic Legos • Nuclear Legos • Particle-Physics Legos • Mathematical Legos • Photon Legos • Above the Law? • Quanta and Rainbows • Making Waves • Quantum Weirdness • The Collapse of Consensus • The Weirdness Can’t Be Confined • Quantum Confusion 8 The Level III Multiverse The Level III Multiverse • The Illusion of Randomness • Quantum Censorship • The Joys of Getting Scooped • Why Your Brain Isn’t a Quantum Computer • Subject, Object and Environment • Quantum Suicide • Quantum Immortality? • Multiverses Unified • Shifting Views: Many Worlds or Many Words? Part Three: Stepping Back 9 Internal Reality, External Reality and Consensus Reality External Reality and Internal Reality • The Truth, the Whole Truth and Nothing but the Truth • Consensus Reality • Physics: Linking External to Consensus Reality 10 Physical Reality and Mathematical Reality Math, Math Everywhere! • The Mathematical Universe Hypothesis • What Is a Mathematical Structure? 11 Is Time an Illusion? How Can Physical Reality Be Mathematical? • What Are You? • Where Are You? (And What Do You Perceive?) • When Are You? 12 The Level IV Multiverse Why I Believe in the Level IV Multiverse • Exploring the Level IV Multiverse: What’s Out There? • Implications of the Level IV Multiverse • Are We Living in a Simulation? • Relation Between the MUH, the Level IV Multiverse and Other Hypotheses •Testing the Level IV Multiverse 13 Life, Our Universe and Everything How Big Is Our Physical Reality? • The Future of Physics • The Future of Our Universe—How Will It End? • The Future of Life •The Future of You—Are You Insignificant? Acknowledgments Suggestions for Further Reading Index

    While they're at it, they helpfully demystify many complicated things we do know about, from quarks and neutrinos to gravitational waves and exploding black holes. With equal doses of humor and delight, they invite us to see the universe as a vast expanse of mostly uncharted territory that's still ours to explore.This entertaining illustrated science primer is the perfect book for anyone who's curious about all the big questions physicists are still trying to answer.

    Beginning with the publication of Albert Einstein's theory of relativity, through the wild revolution of quantum mechanics, and up until the physics of the modern day (including the astonishing revelation, in 1998, that the Universe is not only expanding, but doing so at an ever-quickening pace), much of what physicists have seen in our Universe suggests that much of our Universe is unseen—that we live in a dark cosmos.Everyone knows that there are things no one can see—the air you're breathing, for example, or, to be more exotic, a black hole. But what everyone does not know is that what we can see—a book, a cat, or our planet—makes up only 5 percent of the Universe. The rest—fully 95 percent—is totally invisible to us; its presence discernible only by the weak effects it has on visible matter around it.This invisible stuff comes in two varieties—dark matter and dark energy. One holds the Universe together, while the other tears it apart. What these forces really are has been a mystery for as long as anyone has suspected they were there, but the latest discoveries of experimental physics have brought us closer to that knowledge. Particle physicist Dan Hooper takes his readers, with wit, grace, and a keen knack for explaining the toughest ideas science has to offer, on a quest few would have ever expected: to discover what makes up our dark cosmos.

      In the past few years, a handful of scientists have been in a race to explain a disturbing aspect of our universe: only 4 percent of it consists of the matter that makes up you, me, our books, and every planet, star, and galaxy. The rest—96 percent of the universe—is completely unknown.   Richard Panek tells the dramatic story of how scientists reached this conclusion, and what they’re doing to find this "dark" matter and an even more bizarre substance called dark energy. Based on in-depth, on-site reporting and hundreds of interviews—with everyone from Berkeley’s feisty Saul Perlmutter and Johns Hopkins’s meticulous Adam Riess to the quietly revolutionary Vera Rubin—the book offers an intimate portrait of the bitter rivalries and fruitful collaborations, the eureka moments and blind alleys, that have fueled their search, redefined science, and reinvented the universe.

    But are there limits to what we can discover about our physical universe?In this very personal journey to the edges of knowledge, Marcus du Sautoy investigates how leading experts in fields from quantum physics and cosmology, to sensory perception and neuroscience, have articulated the current lie of the land. In doing so, he travels to the very boundaries of understanding, questioning contradictory stories and consulting cutting edge data.Is it possible that we will one day know everything? Or are there fields of research that will always lie beyond the bounds of human comprehension? And if so, how do we cope with living in a universe where there are things that will forever transcend our understanding?In What We Cannot Know, Marcus du Sautoy leads us on a thought-provoking expedition to the furthest reaches of modern science. Prepare to be taken to the edge of knowledge to find out if there’s anything we truly cannot know.

    There are deep connections between stars and atoms, between the cosmos and the microworld. Just six numbers, imprinted in the "big bang," determine the essential features of our entire physical world. Moreover, cosmic evolution is astonishingly sensitive to the values of these numbers. If any one of them were "untuned," there could be no stars and no life. This realization offers a radically new perspective on our universe, our place in it, and the nature of physical laws.

    Having just completed his masterpiece, The General Theory of Relativity—which provided a brand-new theory of gravity and promised a new perspective on the cosmos as a whole—he set out at once to share his excitement with as wide a public as possible in this popular and accessible book.Here published for the first time as a Penguin Classic, this edition of Relativity features a new introduction by bestselling science author Nigel Calder.

    The rest is known as dark matter and dark energy, because their precise identities are unknown. "The Cosmic Cocktail" is the inside story of the epic quest to solve one of the most compelling enigmas of modern science--what is the universe made of?--told by one of today's foremost pioneers in the study of dark matter.Blending cutting-edge science with her own behind-the-scenes insights as a leading researcher in the field, acclaimed theoretical physicist Katherine Freese recounts the hunt for dark matter, from the discoveries of visionary scientists like Fritz Zwicky--the Swiss astronomer who coined the term "dark matter" in 1933--to the deluge of data today from underground laboratories, satellites in space, and the Large Hadron Collider. Theorists contend that dark matter consists of fundamental particles known as WIMPs, or weakly interacting massive particles. Billions of them pass through our bodies every second without us even realizing it, yet their gravitational pull is capable of whirling stars and gas at breakneck speeds around the centers of galaxies, and bending light from distant bright objects. Freese describes the larger-than-life characters and clashing personalities behind the race to identify these elusive particles.Many cosmologists believe we are on the verge of solving the mystery. "The Cosmic Cocktail" provides the foundation needed to fully fathom this epochal moment in humankind's quest to understand the universe.

    Whether they've arrived via rocket, flying saucer, or plain old teleportation, they've been invading, infiltrating, or inspiring us for decades, and they've fascinated moviegoers and television watchers for more than fifty years. About half of us believe that aliens really exist, and millions are convinced they've visited Earth. For twenty-five years, SETI has been looking for the proof, and as the program's senior astronomer, Seth Shostak explains in this engrossing book, it's entirely possible that before long conclusive evidence will be found. His informative, entertaining report offers an insider's view of what we might realistically expect to discover light-years away among the stars. Neither humanoids nor monsters, says Shostak; in fact, biological intelligence is probably just a precursor to machine beings, enormously advanced artificial sentients whose capabilities and accomplishments may have developed over billions of years and far exceed our own. As he explores what, if anything, they would tell us and what their existence would portend for humankind and the cosmos, he introduces a colorful cast of characters and provides a vivid, state-of-the-art account of the past, present, and future of our search for extraterrestrial intelligence.

    For even as she sets out to determine how big “really big” may be, Levin gives us an intimate look at the day-to-day life of a globe-trotting physicist, complete with jet lag and romantic disturbances.Nimbly synthesizing geometry, topology, chaos and string theories, Levin shows how the pattern of hot and cold spots left over from the big bang may one day reveal the size and shape of the cosmos. She does so with such originality, lucidity—and even poetry—that How the Universe Got Its Spots becomes a thrilling and deeply personal communication between a scientist and the lay reader.