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.

    This seminal work is reproduced here for a whole new generation to enjoy. In Sagan's typically lucid and lyrical style, he discusses many topics from astrophysics and solar system science, to colonization, terraforming and the search for extraterrestrials. Sagan conveys his own excitement and wonder, and relates the revelations of astronomy to the most profound human problems and concerns: issues that are just as valid today as they were thirty years ago. New to this edition are Freeman Dyson's comments on Sagan's vision and the importance of the work, Ann Druyan's assessment of Sagan's cultural significance as a champion of science, and David Morrison's discussion of the advances made since 1973 and what became of Sagan's predictions. Who knows what wonders this third millennium will reveal, but one thing is certain: Carl Sagan played a unique role in preparing us for them.

     Where are we? Who are we? Are our emotions, our beliefs, and our hopes and dreams ultimately meaningless out there in the void? Does human purpose and meaning fit into a scientific worldview?In short chapters filled with intriguing historical anecdotes, personal asides, and rigorous exposition, readers learn the difference between how the world works at the quantum level, the cosmic level, and the human level--and then how each connects to the other.  Carroll's presentation of the principles that have guided the scientific revolution from Darwin and Einstein to the origins of life, consciousness, and the universe is dazzlingly unique.Carroll shows how an avalanche of discoveries in the past few hundred years has changed our world and what really matters to us. Our lives are dwarfed like never before by the immensity of space and time, but they are redeemed by our capacity to comprehend it and give it meaning.The Big Picture is an unprecedented scientific worldview, a tour de force that will sit on shelves alongside the works of Stephen Hawking, Carl Sagan, Daniel Dennett, and E. O. Wilson for years to come.

    Astrophysicist Adam Frank traces the question of alien life and intelligence from the ancient Greeks to the leading thinkers of our own time, and shows how we as a civilization can only hope to survive climate change if we recognize what science has recently discovered: that we are just one of ten billion trillion planets in the Universe, and it’s highly likely that many of those planets hosted technologically advanced alien civilizations. What’s more, each of those civilizations must have faced the same challenge of civilization-driven climate change.Written with great clarity and conviction, Light of the Stars builds on the inspiring work of pioneering scientists such as Frank Drake and Carl Sagan, whose work at the dawn of the space age began building the new science of astrobiology; Jack James, the Texas-born engineer who drove NASA’s first planetary missions to success; Vladimir Vernadsky, the Russian geochemist who first envisioned the Earth’s biosphere; and James Lovelock and Lynn Margulis, who invented Gaia theory. Frank recounts the perilous journey NASA undertook across millions of miles of deep space to get its probes to Venus and Mars, yielding our first view of the cosmic laws of planets and climate that changed our understanding of our place in the universe.Thrilling science at the grandest of scales, Light of the Stars explores what may be the largest question of all: What can the likely presence of life on other worlds tell us about our own fate?

    Enjoy a thrilling intergalactic tour as Andrew Thomas redefines the force of gravity and introduces a brave new view of the universe!

    Accordingly, he once derided as "spooky action at a distance" the notion that two elementary particles far removed from each other could nonetheless influence each other's properties—a hypothetical phenomenon his fellow theorist Erwin Schrödinger termed "quantum entanglement."In a series of ingenious experiments conducted in various locations—from a dank sewage tunnel under the Danube River to the balmy air between a pair of mountain peaks in the Canary Islands—the author and his colleagues have demonstrated the reality of such entanglement using photons, or light quanta, created by laser beams. In principle the lessons learned may be applicable in other areas, including the eventual development of quantum computers.

    QED--the edited version of four lectures on quantum electrodynamics that Feynman gave to the general public at UCLA as part of the Alix G. Mautner Memorial Lecture series--is perhaps the best example of his ability to communicate both the substance and the spirit of science to the layperson.The focus, as the title suggests, is quantum electrodynamics (QED), the part of the quantum theory of fields that describes the interactions of the quanta of the electromagnetic field-light, X rays, gamma rays--with matter and those of charged particles with one another. By extending the formalism developed by Dirac in 1933, which related quantum and classical descriptions of the motion of particles, Feynman revolutionized the quantum mechanical understanding of the nature of particles and waves. And, by incorporating his own readily visualizable formulation of quantum mechanics, Feynman created a diagrammatic version of QED that made calculations much simpler and also provided visual insights into the mechanisms of quantum electrodynamic processes.In this book, using everyday language, spatial concepts, visualizations, and his renowned "Feynman diagrams" instead of advanced mathematics, Feynman successfully provides a definitive introduction to QED for a lay readership without any distortion of the basic science. Characterized by Feynman's famously original clarity and humor, this popular book on QED has not been equaled since its publication.

    David Peat explains the development and meaning of this Superstring Theory in a thoroughly readable, dramatic manner accessible to lay readers with no knowledge of mathematics. The consequences of the Superstring Theory are nothing less than astonishing.

    Every technology we rely on today was created by the human mind, seeking to understand the universe around us. Scientific knowledge is our most precious possession, and our future will be shaped by the breakthroughs to come. In this personal and fascinating work, Neil Turok, Director of the Perimeter Institute for Theoretical Physics, explores the transformative scientific discoveries of the past three centuries -- from classical mechanics, to the nature of light, to the bizarre world of the quantum, and the evolution of the cosmos. Each new discovery has, over time, yielded new technologies causing paradigm shifts in the organization of society. Now, he argues, we are on the cusp of another major transformation: the coming quantum revolution that will supplant our current, dissatisfying digital age. Facing this brave new world, Turok calls for creatively re-inventing the way advanced knowledge is developed and shared, and opening access to the vast, untapped pools of intellectual talent in the developing world. Scientific research, training, and outreach are vital to our future economy, as well as powerful forces for peaceful global progress.

    "One of today's best popularizers of science." —Kirkus Reviews.Loyal readers of the monthly "Universe" essays in Natural History magazine have long recognized Neil deGrasse Tyson's talent for guiding them through the mysteries of the cosmos with stunning clarity and almost childlike enthusiasm. Here, Tyson compiles his favorite essays across a myriad of cosmic topics. The title essay introduces readers to the physics of black holes by explaining the gory details of what would happen to your body if you fell into one. "Holy Wars" examines the needless friction between science and religion in the context of historical conflicts. "The Search for Life in the Universe" explores astral life from the frontiers of astrobiology. And "Hollywood Nights" assails the movie industry's feeble efforts to get its night skies right. Known for his ability to blend content, accessibility, and humor, Tyson is a natural teacher who simplifies some of the most complex concepts in astrophysics while simultaneously sharing his infectious excitement about our universe.

    This is a true insider's account of the phenomenon, and lifts the lid not just on classic cases like Roswell and the Rendlesham Forest incident, but on less well known cases too. This groundbreaking and highly controversial book highlights cases from the US, the UK, and the rest of the world, with Nick drawing on his firsthand government experience to reveal what the authorities really know and think about UFOs, alien abductions, crop circles and animal mutilations. Open Skies Closed Minds was featured on Newsnight, serialized in the Daily Mail and reached number three in the hardback non-fiction list, staying in the top ten for ten weeks.

    David Grinspoon, a planetary scientist who has helped to shape modern planetary exploration, brings the subject to a new generation of readers with his reflections on the most recent developments in astrobiology, including NASA's search for life on Mars. In Lonely Planets, he investigates the big questions: How widespread are life and intelligence in the cosmos? Is life on Earth an accident or in some sense the "purpose" of this universe? And how can we, working from the Earth-centric definition of "life," even begin to think about the varieties of life-forms on other planets?Using the topic of extraterrestrial life as a mirror with which to view human beliefs, evolution, history, and aspirations, Grinspoon provides an authoritative scientific narrative of cosmic evolution, along with provocative ruminations on how we fit into the story of the universe. An accessible, lively blend of science, history, philosophy, and personal narrative, Lonely Planets reveals how the search for extraterrestrial life unites our spiritual and scientific quests for connection with the cosmos.

    In this radically revised and updated edition incorporating the latest scientific findings, science writer and cosmologist John Gribbin explores the origins of the Universe and considers its ultimate fate.

    Can you believe that physical reality is created by our observation of it? Physicists were forced to this conclusion, the quantum enigma, by what they observed in their laboratories.Trying to understand the atom, physicists built quantum mechanics and found, to their embarrassment, that their theory intimately connects consciousness with the physical world. Quantum Enigma explores what that implies and why some founders of the theory became the foremost objectors to it. Schr�dinger showed that it absurdly allowed a cat to be in a superposition simultaneously dead and alive. Einstein derided the theory's spooky interactions. With Bell's Theorem, we now know Schr�dinger's superpositions and Einstein's spooky interactions indeed exist.Authors Bruce Rosenblum and Fred Kuttner explain all of this in non-technical terms with help from some fanciful stories and bits about the theory's developers. They present the quantum mystery honestly, with an emphasis on what is and what is not speculation.Physics' encounter with consciousness is its skeleton in the closet. Because the authors open the closet and examine the skeleton, theirs is a controversial book. Quantum Enigma's description of the experimental quantum facts, and the quantum theory explaining them, is undisputed. Interpreting what it all means, however, is controversial.Every interpretation of quantum physics encounters consciousness. Rosenblum and Kuttner therefore turn to exploring consciousness itself--and encounter quantum physics. Free will and anthropic principles become crucial issues, and the connection of consciousness with the cosmos suggested by some leading quantum cosmologists is mind-blowing.Readers are brought to a boundary where the particular expertise of physicists is no longer a sure guide. They will find, instead, the facts and hints provided by quantum mechanics and the ability to speculate for themselves.

    In The Life of the Cosmos, Smolin cuts the Gordian knot of cosmology with a simple, powerful idea: "The underlying structure of our world, " he writes, "is to be found in the logic of evolution." Today's physicists have overturned Newton's view of the universe, yet they continue to cling to an understanding of reality not unlike Newton's own - as a clock, an intricate mechanism, governed by laws which are mathematical and eternally true. Smolin argues that the laws of nature we observe may be in part the result of a process of natural selection which took place before the big bang. Smolin's ideas are based on recent developments in cosmology, quantum theory, relativity and string theory, yet they offer, at the same time, an unprecedented view of how these developments may fit together to form a new theory of cosmology. From this perspective, the lines between the simple and the complex, the fundamental and the emergent, and even between the biological and the physical are redrawn. The result is a framework that illuminates many intractable problems, from the paradoxes of quantum theory and the nature of space and time to the problem of constructing a final theory of physics. As he argues for this new view, Smolin introduces the reader to recent developments in a wide range of fields, from string theory and quantum gravity to evolutionary theory the structure of galaxies. He examines the philosophical roots of controversies in the foundations of physics, and shows how they may be transformed as science moves towardunderstanding the universe as an interrelated, self-constructed entity, within which life and complexity have a natural place, and in which "the occurrence of novelty, indeed the perpetual birth of novelty, can be understood."