Quantum Theory, together with the principles of special and general relativity, constitute a scientific revolution that has profoundly influenced the way in which we think about the universe and the fundamental forces that govern it. The Historical Development of Quantum Theory is a definitive historical study of that scientific work and the human struggles that accompanied it from the beginning. Drawing upon such materials as the resources of the Archives for the History of Quantum Physics, the Niels Bohr Archives, and the archives and scientific correspondence of the principal quantum physicists, as well as Jagdish Mehra's personal discussions over many years with most of the architects of quantum theory, the authors have written a rigorous scientific history of quantum theory in a deeply human context. This multivolume work presents a rich account of an intellectual triumph: a unique analysis of the creative scientific process. The Historical Development of Quantum Theory is science, history, and biography, all wrapped in the story of a great human enterprise. Its lessons will be an aid to those working in the sciences and humanities alike.

A Nobel prize winner, a great man and a great scientist, Erwin Schroedinger has made his mark in physics, but his eye scans a far wider horizon: here are two stimulating and discursive essays which summarize his philosophical views on the nature of the world. Schroedinger's world view, derived from the Indian writings of the Vedanta, is that there is only a single consciousness of which we are all different aspects. He admits that this view is mystical and metaphysical and incapable of logical deduction. But he also insists that this is true of the belief in an external world capable of influencing the mind and of being influenced by it. Schroedinger's world view leads naturally to a philosophy of reverence for life.

Wir werden spater, aus guten Grunden, der einen den Vorzug geben, im Augenblick mussen wir uns mit beiden auseinander- etzen. Die altere und naivere Anwendung bezieht sich auf N wirklich existierende physikalische Systeme, die in wirklicher physikalischer Wechselwirkung miteinander stehen, also z. B. Gasmolekule oder Elektronen oder Plancksche Oszillatoren oder Freiheitsgrade (AtherosziIlatoren) eines "Hohlraumes". Aile N zusammen stellen das betrachtete wirkliche physikalische System dar. Dieser ursprungliche Gesichtspunkt ist an die Namen von MAXWELL, BOLTZMANN und anderen geknupft. Er genugt aber nur zur Behandlung einer sehr beschriinkten Klasse von physikalischen Systemen - in der Tat nur der Gase. Er ist nicht auf ein System anwendbar, das nicht aus einer groBen Anzahl identischer Bestandteile mit "privaten" Ener- gien zusammengesetzt ist. In einem festen Korper ist die Wech- selwirkung zwischen Nachbaratomen so stark, daB man auch nicht gedanklich seine Gesamtenergie in die Privatenergien seiner Atome aufteilen kann, ja schon ein "Hohlraum" (ein "Atherblock" als Sitz der Vorgange im elektromagnetischen Felde) laBt sich nur in OsziIlatoren von vielen - unendlich vie- len - verschiedenen Arten auflosen, so daB es mindestens not- wen dig ware, mit einer Gesamtheit von unendlich vielen ver- schiedenen (weil aus verschiedenen Bestandteilen bestehenden) Gesamtheiten zu arbeiten.

Nobel laureate Erwin Schroedinger was one of the most distinguished scientists of the twentieth century; his lectures on the history and philosophy of science are legendary. 'Nature and the Greeks' and 'Science and Humanism' makes available for the first time in many years the texts of two of Schroedinger's most famous lecture series. 'Nature and the Greeks' offers a comprehensive historical account of the twentieth-century scientific world picture, tracing modern science back to the earliest stages of Western philosophic thought. 'Science and Humanism' addresses some of the most fundamental questions of the century: what is the value of scientific research? And how do the achievements of modern science affect the relationship between material and spiritual matters? A foreword by Roger Penrose sets the lectures in a contemporary context, and affirms they are as relevant today as when they were first published.

Reprint of a classical book first published in 1950. This lucid and profound exposition of Einstein's 1915 theory of gravitation is essential reading.