The year 2000 is alternatively the year 2544 (Buddhist), 6236 (Ancient Egyptian), 5761 (Jewish) or simply the Year of the Dragon (Chinese). The story of the creation of the Western calendar, which is related in this book, is a story of emperors and popes, mathematicians and monks, and the growth of scientific calculation to the point where, bizarrely, our measurement of time by atomic pulses is now more accurate than time itself: the Earth is an elderly lady and slightly eccentric - she loses half a second a century. Days have been invented (Julius Caesar needed an extra 80 days in 46BC), lost (Pope Gregory XIII ditched ten days in 1582) and moved (because Julius Caesar had 31 in his month, Augustus determined that he should have the same, so he pinched one from February).

    In October 2015, NASA declared Mars “an achievable goal”; that same season, Ridley Scott and Matt Damon’s The Martian drew crowds into theaters, grossing over $200 million.Now the National Geographic Channel fast forwards years ahead with Mars, a six-part series documenting and dramatizing the next twenty-five years as humans land on and learn to live on Mars. Following on the visionary success of Buzz Aldrin’s Mission to Mars and the visual glory of Marc Kaufman’s Mars Up Close, this companion book to the Nat Geo series shows the science behind the mission and the challenges awaiting those brave individuals.The book combines science, technology, and storytelling, offering what only National Geographic can create. Clear scientific explanations make the Mars experience real and provide amazing visuals to savor and return to again and again.

    Professor Lofti Zadeh masterminded "fuzzy logic"--a way of programming computers to "make decisions" bases on imprecise data and complex situations. In "Fuzzy Logic," Daniel McNeill and Paul Freiberger relate the compelling tale of this remarkable new technology, the genius who brought it to life, and how it will soon affect the lives of every one of us.

    Smoking has gone from doctor recommended to deadly. We used to think the Earth was the center of the universe and that Pluto was a planet. For decades, we were convinced that the brontosaurus was a real dinosaur. In short, what we know about the world is constantly changing.   But it turns out there’s an order to the state of knowledge, an explanation for how we know what we know. Samuel Arbesman is an expert in the field of scientometrics—literally the science of science. Knowl­edge in most fields evolves systematically and predict­ably, and this evolution unfolds in a fascinating way that can have a powerful impact on our lives.   Doctors with a rough idea of when their knowl­edge is likely to expire can be better equipped to keep up with the latest research. Companies and govern­ments that understand how long new discoveries take to develop can improve decisions about allocating resources. And by tracing how and when language changes, each of us can better bridge gen­erational gaps in slang and dialect.   Just as we know that a chunk of uranium can break down in a measurable amount of time—a radioactive half-life—so too any given field’s change in knowledge can be measured concretely. We can know when facts in aggregate are obsolete, the rate at which new facts are created, and even how facts spread.   Arbesman takes us through a wide variety of fields, including those that change quickly, over the course of a few years, or over the span of centuries. He shows that much of what we know consists of “mesofacts”—facts that change at a middle timescale, often over a single human lifetime. Throughout, he of­fers intriguing examples about the face of knowledge: what English majors can learn from a statistical analysis of The Canterbury Tales, why it’s so hard to measure a mountain, and why so many parents still tell kids to eat their spinach because it’s rich in iron.   The Half-life of Facts is a riveting journey into the counterintuitive fabric of knowledge. It can help us find new ways to measure the world while accepting the limits of how much we can know with certainty.

    No graduate student of quantum theory should leave it unread"--W.C Schieve, University of Texas

    Every massive star leaves behind a black hole when it dies, and every galaxy harbors a supermassive black hole at its center. Frighteningly enigmatic, these dark giants continue to astound even the scientists who spend their careers studying them. Which came first, the galaxy or its central black hole? What happens if you travel into one—instant death or something weirder? And, perhaps most important, how can we ever know anything for sure about black holes when they destroy information by their very nature?In Einstein’s Monsters, distinguished astronomer Chris Impey takes readers on an exploration of these and other questions at the cutting edge of astrophysics, as well as the history of black holes’ role in theoretical physics—from confirming Einstein’s equations for general relativity to testing string theory. He blends this history with a poignant account of the phenomena scientists have witnessed while observing black holes: stars swarming like bees around the center of our galaxy; black holes performing gravitational waltzes with visible stars; the cymbal clash of two black holes colliding, releasing ripples in space-time.Clear, compelling, and profound, Einstein’s Monsters reveals how our comprehension of black holes is intrinsically linked to how we make sense of the universe and our place within it. From the small questions to the big ones—from the tiniest particles to the nature of space-time itself—black holes might be the key to a deeper understanding of the cosmos.

    In the hands of one of today’s hottest young physicists, that simple fact of breakfast becomes a doorway to understanding the Big Bang, the universe, and other universes, too. In From Eternity to Here, Sean Carroll argues that the arrow of time, pointing resolutely from the past to the future, owes its existence to conditions before the Big Bang itself, a period modern cosmology of which Einstein never dreamed. Increasingly, though, physicists are going out into realms that make the theory of relativity seem like child’s play. Carroll’s scenario is not only elegant, it’s laid out in the same easy-to- understand language that has made his group blog, Cosmic Variance, the most popular physics blog on the Net. From Eternity to Here uses ideas at the cutting edge of theoretical physics to explore how properties of spacetime before the Big Bang can explain the flow of time we experience in our everyday lives. Carroll suggests that we live in a baby universe, part of a large family of universes in which many of our siblings experience an arrow of time running in the opposite direction. It’s an ambitious, fascinating picture of the universe on an ultra-large scale, one that will captivate fans of popular physics blockbusters like Elegant Universe and A Brief History of Time.