These articles and speeches by the Nobel Prize-winning physicist date from 1934 to 1958. Rather than expositions on quantum physics, the papers are philosophical in nature, exploring the relevance of atomic physics to many areas of human endeavor. Includes an essay in which Bohr and Einstein discuss quantum and_wave equation theories. 1961 edition.

For this eighth edition he also wrote a new chapter on the quantum theory of solids.

Introduction -- Light and life -- Biology and atomic physics -- Natural philosophy and human cultures -- Discussion with Einstein on epistemological problems in atomic physics -- Unity of knowledge -- Atoms and human knowledge -- Physical science and the problem of life.

ArgumentThis paper discusses one aspect of the context in which atomic physics developed in Japan between 1905 and 1931. It argues that during this period, there was a social context in which atomic physics was valued as a study of the electron and was thus relevant to electrical engineering. To demonstrate this, I first show that after the Russo-Japanese War, electrical engineering was deemed a valuable and viable field of research in Japan. Second, I show that (...) physicists wrote textbooks and popular accounts about the electron, covering topics from both atomic physics and electrical engineering and presenting the former as relevant to the latter. Finally, as an example of how atomic physics partially emerged from this context, I discuss the group of Kujirai Tsunetarō, an electrical engineer who worked in the physics department of the Institute for Physical and Chemical Research. From Kujirai's group, Nishina Yoshio started his career and became the most important Japanese atomic and nuclear physicist of the 1930s. (shrink)

In the long history of science there is nothing quite like the famous dialogue which ensued between Albert Einstein and Neils Bohr about the validity and meaning of the new quantum theory. By 1927 when the first public debate took place, both men stood at the top of their profession. Einstein was the creator of the Special and General theories of relativity and also had made major contributions to atomic theory. Bohr had developed the successful model of the hydrogen (...) atom in 1913 and his two principles of correspondence and complementarity had established the relationship between classical physics and the new physics of the atom. MacKinnon treats this Bohr-Einstein dialogue as the centerpiece and climax of his book on the history of Atomism from a philosophical perspective. It is a carefully written and closely argued discussion of the contributions of significant scientists and philosophers of science to the perennial question about nature: is it made up of discrete nonreducible parts or is it continuous and infinitely divisible? (shrink)

A theory, analogous with the kinetic theory of heat, is described, in which the role of heat is shared by all the phenomena of extra-atomic physics, including quantum electrodynamics, gravitation, and relativistic mass. The role of the randomly moving molecules, as a mechanical model, is taken for all of these by a single model, consisting of a turbulent, dissipationless liquid, the motion of which conforms to Newtonian mechanics. This model is capable of supporting spherical standing waves which are (...) taken to represent elementary particles. The mechanical counterparts of the physical equations are close approximations to those of the model. (shrink)

"It remains unforeseeable why any recalcitrance should prevail where an attempt is being made towards the inclusion of concepts stressing finitude," Murdy writes. "After all, why such a view should be wrathed by subordination in preference to aspects of ad infinitum, is difficult to ascertain, especially so, if postulates conveying the impression of infinity are besieged by so many unknown factors".--R. P.

We provide a detailed history of the concepts of atomic number and isotopy before the discovery of protons and neutrons that draws attention to the role of evolving interplays of multiple aims and criteria in chemical and physical research. Focusing on research by Frederick Soddy and Ernest Rutherford, we show that, in the context of differentiating disciplinary projects, the adoption of a complex and shifting concept of elemental identity and the ordering role of the periodic table led to a (...) relatively coherent notion of atomic number. Subsequent attention to valency, still neglected in the secondary literature, and to nuclear charge led to a decoupling of the concepts of elemental identity and weight and allowed for a coherent concept of isotopy. This concept received motivation from empirical investigations on the decomposition series of radioelements and their unstable chemical identity. A new model of chemical order was the result of an ongoing collaboration between chemical and physical research projects with evolving aims and standards. After key concepts were considered resolved and their territories were clarified, chemistry and physics resumed autonomous projects, yet remained bound by newly accepted explanatory relations. It is an episode of scientific collaboration and partial integration without simple, wholesale gestalt switches or chemical revolutions. (shrink)

Physics, History, and the German Atomic Bomb. This paper examines the German concept of a nuclear weapon during National Socialism and the Second World War. Zusammenfassung: Physik, Geschichte und die deutsche Atombombe. Dieser Aufsatz untersucht die deutsche Vorstellung einer nuklearen Waffe während des Nationalsozialismus und des Zweiten Weltkrieges.

This paper suggests that the cases made for atoms and the aether in nineteenth-century physical science were analogous, with the implication that the case for the atom was less than compelling, since there is no aether. It is argued that atoms did not play a productive role in nineteenth-century chemistry any more than the aether did in physics. Atoms and molecules did eventually find an indispensable home in chemistry but by the time that they did so they were different (...) kinds of entities to those figuring in the speculations of those natural philosophers who were atomists. Advances in nineteenth-century chemistry were a precondition for rather than the result of the productive introduction of atoms into chemistry. (shrink)

This book reconstructs the kalām theories of matter, space, and void in the tenth and eleventh centuries A.D., using texts that have only recently become available.

In this paper we analyse the approach to interpreting atomic spectra in the framework of classical physics from the discovery of the electron in 1897 to Bohr's atomic model of 1913. Taken as a whole, efforts in this direction are part of a remarkable intellectual endeavour in which the classical theoretical framework seems to have been exploited to its full potential. By demonstrating the limits and weaknesses of classical physics in solving the problem of spectral emissions, (...) these attempts opened the way to a complete break from traditional thought and the introduction of the new quantum ideas. (shrink)

Written by Sadri Hassani, the author of several mathematical physics textbooks, this work covers the essentials of modern physics, in a way that is as thorough ...

This book reexamines the birth of quantum mechanics, in particular examining the development of crucial and original insights of Bohr. In particular, it gives a detailed study of the development and the interpretation given to Bohr's Principle of Correspondence. It also describes the role that this principle played in guiding Bohr's research over the critical period from 1920 to 1927.

Zusammenfassung: Fehlinterpretierte Dokumente und ignorierte physikalische Fakten: Die Geschichte von,Hitlers Atombombe‘ muss korrigiert werden. Warum haben die deutschen Physiker während des Zweiten Weltkriegs keine Atombombe entwickelt? Seit mehr als 25 Jahren sind sich die Historiker einig, dass die deutschen Physiker wussten, wie eine Atombombe gebaut werden muss, dass aber ein Programm wie das amerikanische Manhattan‐Projekt zu ihrer Realisierung in Deutschland, erst recht während des Krieges, unmöglich war. Eine genaue Analyse aller erhaltenen Original‐Dokumente über die Arbeit an der Atombombe während des,Dritten (...) Reichs‘ zeigt jedoch erhebliche Fehler der Autoren durch unvollständige Analyse der Dokumente, falsches Verständnis naturwissenschaftlicher Erläuterungen und Ignorieren physikalischer Fakten. Es wird nachgewiesen, dass die deutschen Physiker bis zum Ende des Krieges nicht bemerkt hatten, dass eine Atombombe nur mit schnellen Neutronen realisiert werden kann. Nur Heisenberg hatte das richtige Prinzip spät erkannt, es aber nicht eindeutig kommuniziert und auch in keiner Weise physikalisch vertieft. Die physikalisch korrekte Interpretation der Dokumente zeigt, dass die deutschen Physiker während des Krieges erfolglos versuchten, einen Reaktor zu entwickeln, der auch eine Voraussetzung für den Bau einer Plutonium‐Bombe gewesen wäre. Aber sie wussten nicht, wie eine Bombe realisiert werden kann, weil sie nie an einer realistischen Theorie der Atombombe gearbeitet hatten. Summary: Misinterpreted Documents and Ignored Physical Facts: The History of ‘Hitler's Atomic Bomb’ needs to be corrected. Why have the German physicists not developed an atomic bomb during World War II? For more than 25 years, the historians agree that they knew how to build the bomb, but that a bomb‐development programme of the size of the US‐Manhattan‐Project would not have been possible in wartime Germany. A detailed analysis of all preserved documents on the German atomic bomb research during the ‘Third Reich’, however, reveals considerable mistakes by the authors due to incomplete analysis of documents, misinterpretations of scientific explanations and ignoring of physical facts. It is shown that until the end of the war the German physicists did not know that an atomic bomb can only be made with fast neutrons, except Heisenberg, who, however, discovered it rather late, did not communicate it clearly and did not study any bomb physics. The physically correct interpretation of the documents reveals that the German physicists worked unsuccessfully on a reactor, which would have been a prerequisite for a plutonium bomb. But they did not know how to build a bomb because they never worked on a realistic bomb theory. (shrink)

Zusammenfassung: Fehlinterpretierte Dokumente und ignorierte physikalische Fakten: Die Geschichte von,Hitlers Atombombe‘ muss korrigiert werden. Warum haben die deutschen Physiker während des Zweiten Weltkriegs keine Atombombe entwickelt? Seit mehr als 25 Jahren sind sich die Historiker einig, dass die deutschen Physiker wussten, wie eine Atombombe gebaut werden muss, dass aber ein Programm wie das amerikanische Manhattan‐Projekt zu ihrer Realisierung in Deutschland, erst recht während des Krieges, unmöglich war. Eine genaue Analyse aller erhaltenen Original‐Dokumente über die Arbeit an der Atombombe während des,Dritten (...) Reichs‘ zeigt jedoch erhebliche Fehler der Autoren durch unvollständige Analyse der Dokumente, falsches Verständnis naturwissenschaftlicher Erläuterungen und Ignorieren physikalischer Fakten. Es wird nachgewiesen, dass die deutschen Physiker bis zum Ende des Krieges nicht bemerkt hatten, dass eine Atombombe nur mit schnellen Neutronen realisiert werden kann. Nur Heisenberg hatte das richtige Prinzip spät erkannt, es aber nicht eindeutig kommuniziert und auch in keiner Weise physikalisch vertieft. Die physikalisch korrekte Interpretation der Dokumente zeigt, dass die deutschen Physiker während des Krieges erfolglos versuchten, einen Reaktor zu entwickeln, der auch eine Voraussetzung für den Bau einer Plutonium‐Bombe gewesen wäre. Aber sie wussten nicht, wie eine Bombe realisiert werden kann, weil sie nie an einer realistischen Theorie der Atombombe gearbeitet hatten. Summary: Misinterpreted Documents and Ignored Physical Facts: The History of ‘Hitler's Atomic Bomb’ needs to be corrected. Why have the German physicists not developed an atomic bomb during World War II? For more than 25 years, the historians agree that they knew how to build the bomb, but that a bomb‐development programme of the size of the US‐Manhattan‐Project would not have been possible in wartime Germany. A detailed analysis of all preserved documents on the German atomic bomb research during the ‘Third Reich’, however, reveals considerable mistakes by the authors due to incomplete analysis of documents, misinterpretations of scientific explanations and ignoring of physical facts. It is shown that until the end of the war the German physicists did not know that an atomic bomb can only be made with fast neutrons, except Heisenberg, who, however, discovered it rather late, did not communicate it clearly and did not study any bomb physics. The physically correct interpretation of the documents reveals that the German physicists worked unsuccessfully on a reactor, which would have been a prerequisite for a plutonium bomb. But they did not know how to build a bomb because they never worked on a realistic bomb theory. (shrink)

We examine the compromises that are actually made in modern scientific discourse concerning atoms. We conclude that even the ideals of clarity and consistency can be legitimately compromised in order to obtain other advantages.