Clear Science Teaching to Set the Stage for an Awe-Inspiring Course Created for a lay audience and readily accessible, in this course science always takes precedence over drama. The lectures are certainly entertaining, often funny, even awe-inspiring at times, as befits the subject matter. Even though you will be entertained, you will be learning good science. Clear introductions to essential principles of physics support these lectures, including density, quantum theory, gravity, and the General Theory of Relativity. Professor Neil deGrasse Tyson also includes forays into disciplines such as chemistry and biology as needed to explain events in astronomy. For example, Dr. Tyson begins one lecture at a point 13 billion years ago, when all space, matter, and energy in the known universe were contained in a volume less than one-trillionth the size of a pinpoint-about the size of a single atom. By the time he finishes, the cosmos has been stretched, the planets and our Earth formed, and 70 percent of existing Earth species have been wiped out by a gigantic asteroidclearing the way for the evolution of humanity. Along the way he has touched on Einstein's famous equation, E=mc2; on the four forces that were once unified in the early cosmos in a way physicists are still trying to explain; and on the chemical enrichment of the universe by exploding supernovae, which give the universe its necessary supply of heavier elements including oxygen, nitrogen, iron and, most important, carbon. Carbon, we learn, is a "sticky" atom, capable of making more kinds of molecules than all other elements combined. It's the ideal element with which to experiment in the building of life forms and is, of course, the element responsible for the remarkable diversity of life, including us. As Dr. Tyson notes, we are made of stardust, just as the planets are. And he has created a course that explains exactly how that came to be, beginning with a grounding in the basic "machinery" of matter, forces, and energy that has been discovered on Earth and which also reveals itself throughout the universe. The Stark and Violent Beauty of the Universe With this basic foundation in place, explanations of cosmic events fall logically into place, and the realities of the universe-including its eventual demise-are revealed in stark and often violent beauty. You learn: how Saturn's rings were formed, and why they will eventually be lost why low-density conditions are necessary to produce the drama of the northern and southern auroras why even the most jagged and wild of the Earth's mountain ranges are, from a cosmic standpoint, really part of a perfectly smooth sphere how black holes are formed and the extraordinary way in which they can wreak havoc in the universe how asteroids moving through space represent threats of extraordinary consequence to Earth, no matter how long those threats may take to be realized why the seemingly infinite panorama of celestial bodies revealed by the Hubble Space Telescope's famous "Deep Field" so intrigued astronomers how astronomers actually look for new planets, why the odds seem overwhelmingly in favor of some kind of life out there, whether we ever make contact or not. Most important, none of these ideas are presented as isolated "space factoids" that serve no purpose but to entertain. They are there to illustrate and reinforce the key principles of physics and astrophysics that are continually being presented in this course. But the inclusion of real science doesn't prevent Dr. Tyson from having some fun, either. When it's time to show how a black hole might remove one from the universe, he leads you right up to the "event horizon" and slips you in-feet first. Since the event horizon represents the point within which nothing, not even light, can escape, you might think this is a bad idea. And you would be right. But as you plummet toward the "singularity" at the heart of the black hole, you will learn firsthand about the interesting effects of gravity truly unleashed, including what physicists refer to, with a straight face, as "spaghettification." (Actually, Professor Tyson recommends that you be sucked in to a large black hole rather than a small one. You'll still be spaghettified, but it won't happen as quickly.) But make no mistake: Dr. Tyson does not consider the cosmos a laughing matter, this kind of whimsical touch notwithstanding. In spite of his training, he remains, admittedly, still in awe of his subject. And he has created a course that might well produce the same feeling in you.

    Relativity and quantum physics touch the very basis of physical reality, altering our commonsense notions of space and time, cause and effect. Both have reputations for complexity. But the basic ideas behind relativity and quantum physics are, in fact, simple and comprehensible by anyone. As Professor Wolfson points out, the essence of relativity can be summed up in a single sentence: The laws of physics are the same for all observers in uniform motion. The same goes for quantum theory, which is based on the principle that the "stuff " of the universe-matter and energy-is not infinitely divisible but comes in discrete chunks called "quanta." Profound ... Beautiful ... Relevant Why should you care about these landmark theories? Because relativity and quantum physics are not only profound and beautiful ideas in their own right, they are also the gateway to understanding many of the latest science stories in the media. These are the stories about time travel, string theory, black holes, space telescopes, particle accelerators, and other cutting-edge developments. Consider these ideas: Although Einstein's theory of general relativity dates from 1914, it has not been possible to test certain predictions until recently. The Hubble Space Telescope is providing some of the most striking confirmations of the theory, including certain evidence for the existence of black holes, objects that warp space and time so that not even light can escape. Also, the expansion of the universe predicted by the theory of general relativity is now a known rate. General relativity also predicts an even weirder phenomenon called "wormholes" that offer shortcuts to remote reaches of time and space. According to Einstein's theory of special relativity, two twins would age at different rates if one left on a high-speed journey to a distant star and then returned. This experiment has actually been done, not with twins, but with an atomic clock flown around the world. Another fascinating experiment confirming that time slows as speed increases comes from measuring muons at the top and bottom of mountains. A seemingly absurd consequence of quantum mechanics, called "quantum tunneling," makes it possible for objects to materialize through impenetrable barriers. Quantum tunneling happens all the time on the subatomic scale and plays an important role in electronic devices and the nuclear processes that keep the sun shining. Some predictions about the expansion of the universe were so odd that Einstein himself tried to rewrite the mathematics in order to eliminate them. When Hubble discovered the expansion of the universe, Einstein called the revisions the biggest mistake he had ever made. An intriguing thought experiment called "Schrödinger's cat" suggests that a cat in an enclosed box is simultaneously alive and dead under experimental conditions involving quantum phenomena. From Aristotle to the Theory of Everything Professor Wolfson begins with a brief overview of theories of physical reality starting with Aristotle and culminating in Newtonian or "classical" physics. Then he outlines the logic that led to Einstein's theory of special relativity, and the simple yet far-reaching insight on which it rests. With that insight in mind, you move on to consider Einstein's theory of general relativity and its interpretation of gravitation in terms of the curvature of space and time. Professor Wolfson then shows how inquiry into matter at the atomic and subatomic scales led to quandaries that are resolved-or at least clarified-by quantum mechanics, a vision of physical reality so at odds with our experience that it nearly defies language. Bringing relativity and quantum mechanics into the same picture leads to hypotheses about the origin, development, and possible futures of the entire universe, and the possibility that physics can produce a "theory of everything" to account for all aspects of the physical world. Fascinating Incidents and Ideas Along the way, you'll explore these fascinating incidents and ideas: In the 1880s, Albert Michelson and Edward Morley conducted an experiment to determine the motion of the Earth relative to the ether, which was a supposedly imponderable substance pervading all of space. You'll learn about their experiment, its shocking result, and the resulting theoretical crisis. In 1905, a young Swiss patent clerk named Albert Einstein resolved the crisis by discarding the ether concept and asserting the principle of relativity-that the laws of physics are the same for all observers in uniform motion. Relativity implies that the time order of events can be different in different reference frames. Does this wreak havoc with cause and effect? And why does Einstein assert that nothing can go faster than light? Shortly after publishing his 1905 paper on special relativity, Einstein realized that his theory required a fundamental equivalence between mass and energy, which he expressed in the equation E=mc2. Among other things, this famous formula means that the energy contained in a single raisin could power a large city for a whole day. Historically, the path to general relativity followed Einstein's attempt to incorporate gravity into relativity theory, which led to his understanding of gravity not as a force, but as a local manifestation of geometry in curved spacetime. Quantum theory places severe limits on our ability to observe nature at the atomic scale because it implies that the act of observation necessarily disturbs the thing that is being observed. The result is Werner Heisenberg's famous "uncertainty principle." Are quarks, the particles that make up protons and neutrons, the truly elementary particles? What are the three fundamental forces that physicists identify as holding particles together? Could they be manifestations of a single, universal force? A Teaching Legend On his own Middlebury College campus, Professor Wolfson is a teaching legend with an infectious enthusiasm for his subject and a knack for conveying difficult concepts in a way that fosters true understanding. He is the author of an introductory text on physics, a contributor to the esteemed publication Scientific American, and a specialist in interpreting science for the nonspecialist. In this course, Professor Wolfson uses extensive illustrations and diagrams to help bring to life the theories and concepts that he discusses. Thus we highly recommend our DVD version, although Professor Wolfson is mindful of our audio students and carefully describes visual materials throughout his lectures. Professor Richard Wolfson on the Second Edition of Einstein's Relativity: "The first version of this course was produced in 1995. In this new version, I have chosen to spend more time on the philosophical interpretation of quantum physics, and on recent experiments relevant to that interpretation. I have also added a final lecture on the theory of everything and its possible implementation through string theory. The graphic presentations for the DVD version have also been extensively revised and enhanced. But the goal remains the same: to present the key ideas of modern physics in a way that makes them clear to the interested layperson."

    Kaku skillfully guides us through the latest innovations in string theory and its latest iteration, M-theory, which posits that our universe may be just one in an endless multiverse, a singular bubble floating in a sea of infinite bubble universes. If M-theory is proven correct, we may perhaps finally find answer to the question, “What happened before the big bang?” This is an exciting and unforgettable introduction into the new cutting-edge theories of physics and cosmology from one of the pre-eminent voices in the field.

    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

    Everything. Yet, in recent years discoveries in physics and cosmology have led a number of scientists to conclude that our universe may be one among many. With crystal-clear prose and inspired use of analogy, Brian Greene shows how a range of different “multiverse” proposals emerges from theories developed to explain the most refined observations of both subatomic particles and the dark depths of space: a multiverse in which you have an infinite number of doppelgängers, each reading this sentence in a distant universe; a multiverse comprising a vast ocean of bubble universes, of which ours is but one; a multiverse that endlessly cycles through time, or one that might be hovering millimeters away yet remains invisible; another in which every possibility allowed by quantum physics is brought to life. Or, perhaps strangest of all, a multiverse made purely of math.Greene, one of our foremost physicists and science writers, takes us on a captivating exploration of these parallel worlds and reveals how much of reality’s true nature may be deeply hidden within them. And, with his unrivaled ability to make the most challenging of material accessible and entertaining, Greene tackles the core question: How can fundamental science progress if great swaths of reality lie beyond our reach?Sparked by Greene’s trademark wit and precision, The Hidden Reality is at once a far-reaching survey of cutting-edge physics and a remarkable journey to the very edge of reality—a journey grounded firmly in science and limited only by our imagination.

    Here he explains how our image of the world has changed throughout centuries. Fom Aristotle to Albert Einstein, Michael Faraday to the Higgs boson, he takes us on a wondrous journey to show us that beyond our ever-changing idea of reality is a whole new world that has yet to be discovered.

    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.

    Breaking down the symbols themselves, they pose a series of questions: What is energy? What is mass? What has the speed of light got to do with energy and mass? In answering these questions, they take us to the site of one of the largest scientific experiments ever conducted. Lying beneath the city of Geneva, straddling the Franco-Swiss boarder, is a 27 km particle accelerator, known as the Large Hadron Collider. Using this gigantic machine—which can recreate conditions in the early Universe fractions of a second after the Big Bang—Cox and Forshaw will describe the current theory behind the origin of mass.Alongside questions of energy and mass, they will consider the third, and perhaps, most intriguing element of the equation: 'c' - or the speed of light. Why is it that the speed of light is the exchange rate? Answering this question is at the heart of the investigation as the authors demonstrate how, in order to truly understand why E=mc2, we first must understand why we must move forward in time and not backwards and how objects in our 3-dimensional world actually move in 4-dimensional space-time. In other words, how the very fabric of our world is constructed. A collaboration between two of the youngest professors in the UK, Why Does E=mc2? promises to be one of the most exciting and accessible explanations of the theory of relativity in recent years.

    David Christian, professor of history at San Diego State University, surveys the past at all possible scales, from conventional history, to the much larger scales of biology and geology, to the universal scales of cosmology.

    And you'll also learn the "rules of the game" - the forces that drive those particles and the ways in which they interact - that underlie the workings of the universe.The lectures have been designed to be enriching for everyone, regardless of scientific background or mathematical ability. Virtually all you'll need as you enter this fascinating world are your curiosity, common sense, and, as Professor Pollock notes, "an open mind for the occasional quantum weirdness." As you move through the lectures, you'll also gain a knowledge of how those particles fit into perhaps the greatest scientific theory of all time: the Standard Model of particle physics; a grasp of key terms like "gauge symmetry," "quantum chromodynamics," and "unified quantum field Theory;" and an appreciation of how particle physics fits in with other branches of physics - including cosmology and quantum mechanics - to create our overall understanding of nature.

    "The Theory of Everything" presents the most complex theories, both past and present, of physics; yet it remains clear and accessible. It will enlighten readers and expose them to the rich history of scientific thought and the complexities of the universe in which we live.

    Weaving together the cosmos' history and our own in an expanding intellectual adventure story, Dark Matter and the Dinosaurs takes us from the mysteries of dark matter and our cosmic environment to the conditions for life on Earth.Sixty-six million years ago, an object the size of a city descended from space to crash into Earth, creating a cataclysm that killed off the dinosaurs, along with three-quarters of the other species on the planet. What was its origin? Randall proposes it was a comet that was dislodged from its orbit as the Solar System passed through a disk of dark matter that is embedded in the plane of the Milky Way. Her research challenges the usual assumptions about the simple nature of dark matter and demonstrates how scientists formulate and establish new ideas. In a sense, it might have been dark matter that killed the dinosaurs.With her unique and wide-ranging perspective, Randall connects dark matter to the history of the world in the broadest terms. Bringing in pop culture and social and political viewpoints, she shares with us the latest findings—established and speculative—regarding dark matter, the cosmos, the galaxy, asteroids, comets, and impacts, as well as life's development and extinctions. Randall makes clear how connected the planet is to the makeup of the Universe, but also how fragile our place in the Universe, which evolved over billions of years, might be.In this brilliant and fresh exploration of our cosmic environment, Professor Randall explains the underlying science of our world in the breathtaking tale of a Universe in which the small and the large, the visible and the hidden are intimately related. Dark Matter and the Dinosaurs illuminates the deep relationships that are critical to our world as well as the astonishing beauty of the structures and connections that surround us. It's impossible to read this book and look at either Earth or sky again in the same way.

    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.

    The answer: with the essentials. Now, finally satisfy your desire for scientific inquiry in a way that makes this enormous field accessible, understandable, and undeniably captivating. Professor Viskontas boils down the scientific world into 12 key concepts every educated person should know. Devoting two lectures to each concept to give you more time to engage with it, her 24-lecture series is an engaging and enlightening introduction to everything from the behavior of subatomic particles to the latest theories about the Big Bang. Throughout, you'll get accessible looks at key building blocks of scientific knowledge, including brain plasticity, fluid mechanics, electromagnetism, genetics, quantum theory, emergence, evolution, thermodynamics, the Big Bang, and the nature of matter. Each concept is presented in a clear, concise way that will inform and delight you, and that will give you the opportunity to probe the invisible life of living cells, visit the universe seconds after its birth, and much more. Concepts that may have eluded you in school, that you may not be familiar with, or that you simply never appreciated for their intricate beauty are now brought to vivid life in a way that sticks. Welcome to the world of science - reduced to its powerful essence.

    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.