tailieunhanh - The Philosophy of Vacuum Part 2

The Philosophy of Vacuum Part 2. Physicists will find it extremely interesting, covering, as it does, technical subjects in an accessible way. For those with the necessary expertise, this book will provide an illuminating and authoritative exposition of a many-sided subject." -John D. Barrow, Times Literary Supplement. | Introduction 3 was the recognition of the role of space-time geometry that banished the Lorentz ether and restored to the concept of vacuum a certain austerity. Just how this emerged I shall not try to summarize I leave it to Albert Einstein s On the Ether Chapter 1 appearing for the first time in English translation. This paper was written in 1924 following the work of Bose and of Compton but prior to the discovery of quantum mechanics. As an historical review of the theory of ether most particularly from the point of view of general relativity it is very nearly the last document of this kind which dates from the classical era. Strangely enough it is also one of the only foundational surveys in which Einstein may be said to speak for his generation. In the year 1924 the light quantum hypothesis entered the mainstream but by 1926 so too had quantum mechanics Einstein bids us reluctant farewell. However in this paper Einstein makes only limited reference to the light quantum hypothesis when he does it is to call into question the independent reality of the electromagnetic field not the metaphysical assumptions of his critique. In particular he makes no connection between the light quantum and the concept of contiguous action. Events over the next four years transformed this picture out of all recognition. The picture has scarcely stopped changing since. This collection is concerned with many different aspects of quantum theory and the fundamental forces but there is one very simple feature of quantum field theory which has an immediate relevance to the ether and the history with which Einstein is concerned. That is the discovery by Paul Dirac as interpreted and elaborated by Pascual Jordan shortly after that bosons and fermions may be described as excitations of quantum fields whether they be photons electrons or protons. We know what Einstein thought of quantum field theory he was not interested . From this time his attention was focused exclusively on the .