Bücher von Claus Kiefer

The work published by Einstein, Podolsky and Rosen (EPR) in 1935 is a classic in modern physics. It discusses, for the first time, the central feature of the quantum theory: entanglement. In general, systems are intertwined with each other in nature; that is, they have only one common, non-divisible state. This fact is responsible for all the oddities commonly associated with quantum theory, including the famous thought experiments with Schrodinger's cat and Wigner's friend. The entanglement of quantum mechanics plays a central role in experiments with atoms and photons (Nobel Prize 2012 for Haroche and Wineland) and the planned construction of quantum computers. This book presents EPR's original work amplified with a detailed commentary, which examines both the historical context and all aspects of entanglement. In particular, it focuses on the interpretation of quantum theory and its consequences for a basic understanding of nature.

Vier Elementarkräfte kennt unser Universum. Drei betreffen die Ebene der Atome, eine die Planeten und Galaxien. Wie kann man alle vier Kräfte in ein einheitliches Modell bringen? Das ist die spannende Frage, auf die die Physik bislang noch keine Antwort gefunden hat ¿ bislang. Denn die Theorie der Quantengravitation schickt sich an, diese große Frage des Universums zu beantworten. Claus Kiefer nimmt den Leser mit auf eine kurzweilige Reise durch Relativitätstheorie und Quantentheorie, Zeitpfeil und Kosmologie hin zu Quantengravitation und Quantenkosmologie. Er erklärt, was hinter Phänomenen wie Schwarzen Löchern, Schrödingers Katze, Dunkler Energie, Strings und der Wellenfunktion des Universums steckt und skizziert die aufregende neue Theorie und ihre Antwort auf die Schlüsselfrage der modernen Physik.

Decoherence, a concept known only to few physicists when the first edition appeared in 1996, has since become firmly established experimentally and understood theoretically, as well as widely reported in the literature. The major consequences of decoherence are the emergence of "e;classicality"e; in general, superselection rules, the border line between microscopic and macroscopic behavior in molecules and field theory, the emergence of classical spacetime, and the appearance of quantum jumps. The most important new developments in this rapidly evolving field are included in the second edition of this book, which has become a standard reference on the subject. All chapters have been thoroughly revised and updated. New fields of application now addressed span chaos theory, quantum information, neuroscience, primordial fluctuations in cosmology, black holes and string theory, experimental tests, and interpretational issues. While the major part of the book is concerned with environmental decoherence derived from a universal Schrodinger equation, later chapters address related or competing methods, such as consistent histories, open system dynamics, algebraic approaches, and collapse models.