Helge Kragh

"This book details the history of one of astronomy's many spurious objects, the satellite of Venus. First spotted in 1645, the non-existing moon was "observed" more than a dozen times until the late eighteenth century. Although few astronomers believed in the existence of such an object after about 1770, it continued to attract attention for at least another century. However, it has largely disappeared from the history of astronomy, and the rich historical sources have never been exploited. The story of the enigmatic satellite in its proper historical context demonstrates that it was much more than a mere curiosity in the annals of astronomy. Frederick II of Prussia was familiar with it, and so were Bonnet, Kant and Voltaire. The painstaking attempts to either prove or disprove its existence led to the development of many new perspectives both practical and philosophical. The satellite of Venus belongs to the same category as other fictitious celestial bodies (such as the planet Vulcan), yet it had its own life and fascinating historical trajectory. By following this trajectory, the history of planetary astronomy is addressed in a novel way."--book jacket.

For over three millennia, most people could understand the universe only in terms of myth, religion, and philosophy. Between 1920 and 1970, cosmology transformed into a branch of physics. With this remarkably rapid change came a theory that would finally lend empirical support to many long-held beliefs about the origins and development of the entire universe: the theory of the big bang. In this book, Helge Kragh presents the development of scientific cosmology for the first time as a historical event, one that embroiled many famous scientists in a controversy over the very notion of an evolving universe with a beginning in time. In rich detail he examines how the big-bang theory drew inspiration from and eventually triumphed over rival views, mainly the steady-state theory and its concept of a stationary universe of infinite age. . In the 1920s, Alexander Friedmann and Georges Lemaitre showed that Einstein's general relativity equations possessed solutions for a universe expanding in time. Kragh follows the story from here, showing how the big-bang theory evolved, from Edwin Hubble's observation that most galaxies are receding from us, to the discovery of the cosmic microwave background radiation. Sir Fred Hoyle proposed instead the steady-state theory, a model of dynamic equilibrium involving the continuous creation of matter throughout the universe. Although today it is generally accepted that the universe started some ten billion years ago in a big bang, many readers may not fully realize that this standard view owed much of its formation to the steady-state theory. By exploring the similarities and tensions between the theories, Kragh provides the reader with indispensable background for understanding much of today's commentary about our universe.

"The main focus of this book is on the interconnection of two unorthodox scientific ideas, the varying-gravity hypothesis and the expanding-earth hypothesis. As such, it provides a fascinating insight into a nearly forgotten chapter in both the history of cosmology and the history of the earth sciences. The hypothesis that the force of gravity decreases over cosmic time was first proposed by Paul Dirac in 1937. In this book the author examines in detail the historical development of Dirac's hypothesis and its consequences for the structure and history of the earth, the most important of which was that the earth must have been smaller in the past."--Page 4 of cover.

"The first comprehensive one-volume history of twentieth-century physics, the book takes us from the discovery of x-rays in the mid-1890s to superstring theory in the 1990s. Kragh writes about pure science with the expertise of a trained physicist, while keeping the content accessible to nonspecialists and paying careful attention to practical uses of science, ranging from compact disks to bombs. As a historian, Kragh outlines the social and economic contexts that have shaped the field in the twentieth century. He writes, for example, about the impact of the two world wars, the fate of physics under Hitler, Mussolini, and Stalin, the role of military research, the emerging leadership of the United States, and the backlash against science that began in the 1960s. He also shows how the revolutionary discoveries of scientists ranging from Einstein, Planck, and Bohr to Stephen Hawking have been built on the great traditions of earlier centuries."--BOOK JACKET.

Presenting a history of how the universe at large became the object of scientific understanding, this title offers an integrated and comprehensive account of cosmology that covers all major events from Aristotle's Earth-centred cosmos to the discovery of the accelerating universe.

The reception of the periodic system of elements has received little attention among scientists and historians alike. While many historians have studied Mendeleev's discovery of the periodic system, few have analyzed the ways in which the scientific community perceived and employed it. American historian of science Stephen G. Brush concluded that the periodic law had been generally accepted in the United States and Britain, and has suggested the need to extend this study to other countries. In Early Responses to the Periodic System, renowned historians of science Masanori Kaji, Helge Kragh, and Gábor Palló present the first major comparitive analysis on the reception, response, and appropriation of the periodic system of elements among different nation-states. This book examines the history of its pedagogy and popularization in scientific communities, educational sectors, and popular culture from the 1870s to the 1920s. Fifteen notable historians of science explore the impact of Mendeleev's discovery in eleven countries (and one region) central to chemical research, including Russia, Germany, the Czech lands, and Japan, and one of the few nation-states outside the Western world to participate in nineteenth-century scientific research. The collection, organized by nation-state, explores how local actors regarded the new discovery as law, classification, or theoretical interpretation. In addition to discussing the appropriation of the periodic system, the book examines metaphysical reflections of nature based on the periodic system outside the field of chemistry, and considers how far humans can push the categories of "response" and "reception." Early Responses to the Periodic System provides a compelling read for anyone with an interest in the history of chemistry and the Periodic Table of Elements. -- from dust jacket.

" ... Based on a series of interviews that a fictional person conducted with leading astronomers between 1913 and 1965 ... Although the interviews are purely fictional, a product of the author's imagination, they could have taken place in just the way that is described. They are solidly based on historical facts and, moreover, supplemented with careful annotations and references to the literature"--Dustjacket.