This book discusses the latest research ideas with application to frequency standards (e.g. optical clocks) and assesses ideas from previous symposia which have undergone critical analysis.

This book discusses the latest research ideas with application to frequency standards (e.g. optical clocks) and assesses ideas from previous symposia which have undergone critical analysis.

This symposium was a dedication to John L Hall, who was recently awarded the Nobel Prize in Physics, (report below). The symposium was a celebration of his striking career in physics and his impressive record of achievements. Papers included in this volume offer brief and personal glimpses of some of his achievements, the research he inspired, and the great friendships he has built.Nobel Prize Report:John L Hall, a Scientist Emeritus of the National Institute of Standards and Technology and a Fellow of JILA (joint institute of NIST and University of Colorado) has been awarded the 2005 Nobel Prize in Physics.Hall shared the Nobel with Theodor W Hänsch of the Max Planck Institute for Quantum Optics and a professor of physics at Ludwig Maximilians University in Munich, Germany, and Roy J Glauber, a professor of physics at Harvard University.Hall and Hänsch were awarded half the Nobel Prize for their contributions to the development of laser-based precision spectroscopy, including the optical frequency comb technique. An optical frequency comb is generated by a laser specially designed to produce a series of extremely short — a few billionths of a second — equally spaced pulses of light.

Time and matter are the most fundamental concepts in physics and in any science-based description of the world around us. Quantum theory has, however, revealed many novel insights into these concepts in non-relativistic, relativistic and cosmological contexts. The implications of these novel perspectives have been realized and, in particular, probed experimentally only recently. In the papers in this proceedings, these issues are discussed in a truly interdisciplinary fashion from philosophical and historical perspectives. The leading contributors, including Nobel laureates T W H'nsch and G t' Hooft, address both experimental and theoretical issues.

But all the clocks in the city Began to whirr and chime: ’O let not Time deceive you, You cannot conquer Time. W. H. Auden It is hard to think of a subject as rich, complex, and important as time. From the practical point of view it governs and organizes our lives (most of us are after all attached to a wrist watch) or it helps us to wonderfully ?nd our way in unknown territory with the global positioning system (GPS). More generally it constitutes the heartbeat of modern technology. Time is the most precisely measured quantity, so the second de?nes the meter or the volt and yet, nobody knows for sure what it is, puzzling philosophers, artists, priests, and scientists for centuries as one of the enduring enigmas of all cultures. Indeed time is full of contrasts: taken for granted in daily life, it requires sophisticated experimental and theoretical treatments to be accurately “produced. ” We are trapped in its web, and it actually kills us all, but it also constitutes the stuff we need to progress and realize our objectives. There is nothing more boring and monotonous than the tick-tock of a clock, but how many fascinating challenges have physicists met to realize that monotony: Quite a number of Nobel Prize winners have been directly motivated by them or have contributed 1 signi?cantly to time measurement.

This volume covers advances in atomic frequency standards (atomic clocks) from the last several decades. It explains the use of techniques, such as laser optical pumping, coherent population trapping, laser cooling, and electromagnetic and optical trapping, in the implementation of classical microwave and optical atomic frequency standards. The authors describe the basic physics behind the operation of atomic clocks, explore new frequency standards that provide better stability and accuracy than conventional standards, and illustrate the application of atomic clocks in various areas.

Time and matter are the most fundamental concepts in physics and in any science-based description of the world around us. Quantum theory has, however, revealed many novel insights into these concepts in non-relativistic, relativistic and cosmological contexts. The implications of these novel perspectives have been realized and, in particular, probed experimentally only recently. In the papers in this proceedings, these issues are discussed in a truly interdisciplinary fashion from philosophical and historical perspectives. The leading contributors, including Nobel laureates T W Hnnsch and G t'' Hooft, address both experimental and theoretical issues. Sample Chapter(s). Chapter 1: The Measurement to Time with Atomic Clocks (742 KB). Contents: Measuring Time; Causality and Signal Propagation; Coherence and Decoherence; CP and T Violation; Macroscopic Time Reversal and the Arrow of Time; New Paradigms. Readership: Physicists, philosophers and historians of science, graduate students of physics."

It has been recognised recently that the strange features of the quantum world could be used for new information transmission or processing functions such as quantum cryptography or, more ambitiously, quantum computing. These fascinating perspectives renewed the interest in fundamental quantum properties and lead to important theoretical advances, such as quantum algorithms and quantum error correction codes. On the experimental side, remarkable advances have been achieved in quantum optics, solid state physics or nuclear magnetic resonance. This book presents the lecture notes of the Les Houches Summer School on 'Quantum entanglement and information processing'. Following the long tradition of the les Houches schools, it provides a comprehensive and pedagogical approach of the whole field, written by renowned specialists.One major goal of this book is to establish connections between the communities of quantum optics and of quantum electronic devices working in the area of quantum computing. When two communities share the same goals, the universality of physics unavoidably leads to similar developments. However, the communication barrier is often high, and few physicists are able to overcome it. This school has contributed to bridge the existing gap between communities, for the benefit of the future actors in the field of quantum computing. The book thus combines introductory chapters, providing the reader with a sufficiently wide theoretical framework in quantum information, quantum optics and quantum circuits physics, with more specialized presentations of recent theoretical and experimental advances in the field. This structure makes the book accessible to any graduate student having a good knowledge of basic quantum mechanics, and extremely useful to researchers.·Covers quantum optics, solid state physics and NMR implementations·Pedagogical approach combining introductory lectures and advanced chapters·Written by leading experts in the field·Accessible to all graduate students with a basic knowledge of quantum mechanics