From Sundials To Atomic Clocks: Understanding Time And Frequency

From Sundials To Atomic Clocks: Understanding Time And Frequency
by James Jespersen / / / PDF


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Time keeping sounds as a trivial and dull issue to most people but if someone decides to get informed about it, suddenly discovers that it's a very ting and perplexing field. Our everyday life experience has rendered us insensitive to some wonders and mysteries just because we take them from granted. Unfortunately the majority of human minds have lost the pleasure of looking with owe the world that surround us. One of these marvelous mysteries has to do with time and the ways we measure it. These two, the meaning of time and its measurement methods, are so intrinsically connected that even the technical details of time keeping have something metaphysical in them. The book "From Sundials to Atomic Clocks - Understanding Time and Frequency" successfully conveys this metaphysical feeling to the reader without losing the contact with history, technology and the practical implications of time keeping. This book might be small but it is extremely ting and simultaneously funny. It starts with just the right amount of historical information about the evolution of both time keeping methods and the ways our ancestors grasped the elusive meaning of time. Following this brief but necessary presentation, the reader will be informed about the most advanced method of measuring time with atomic clocks and the technical problems that their inventors had to surmount in order to endow these complicated devices with such an extraordinary accuracy. This part of the book is the best proof of the writers' ability to describe with so friendly and ting a way the physics and the subtle principles behind atomic clocks. Accuracy, stability and the phenomenon of resonance are explained to the layman with the most ting and simple ways I've ever found in a book. The presentation of both the atomic and astronomical ways of time measurement is followed by the more everyday but simultaneously technical issue of how the information of accurate time is transferred all around the world. At this point the reader is also informed about how increasingly essential is accurate time keeping not only for research labs but also for the machinery supporting the most important practical aspects of our everyday life. Safe travelling depends upon the level of navigation sophistication which nowadays depends totally on accurate time keeping and time transfer. The stability of our power grid which protects the electrical devices from getting burned is itself heavily depended on generator synchronization issues. The growing demand for reliable high speed communications pushes forward the demand for more accurate time measurement and distribution. Having dealt with all the aforementioned practical issues which prove that time keeping concerns not only astronomers and physicists, the writers begin a wonderful journey for the Big Blue of the metaphysical aspects of the nature of time. Our navigator now is physics which simultaneously poses and tries to answer fundamental questions such as: 1) Does time flow have a direction and how is this proved from modern physics experiments? 2) Is there a limit set by the physical laws upon how accurately we can measure time? 3) Does time have a beginning? 4) What is the relation between time, entropy and free will? The book concludes with the future of time i.e. speculations about more elaborate devices for time keeping. I fully recommend this book which I truly enjoyed reading. It is complete because it deals with almost all aspects of time and their significance for human civilization, technology and thinking. The style of writing is very easy going without becoming simplistic and this is exactly the reason why this is a book for the layman who has knowledge of elementary physics.

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