摘要:

In this talk, I would like to trace the origins of some of the major theoretical and experimental advances which have led to the development of a successful microscopic theory of superconductivity and then to indicate briefly some of the current problems. Fritz London made extremely important contributions to the theory and laid the groundwork for our present understanding. He showed how the Meissner effect and other superconducting properties could be understood as a consequence of quantum effects operating on a macroscopic scale. A striking prediction of his, which only recently has been verified experimentally, is the quantization of flux in a superconducting ring. My own work on superconductivity theory has been influenced greatly by that of Fritz London.

ISSN:0031-9228    

DOI:10.1063/1.3050710

出版商:AIP    

年代:1963

数据来源: AIP

摘要:

A decade and a half ago in Denmark's darkest days those who had taken her liberty were trying to snuff out her soul. To overwhelming force, the people of the country and their king presented unbending moral resistance. At the center of their spiritual unity stood Denmark's men of learning under the leadership of Niels Bohr. What does it mean to preserve a nation's soul? What makes a nation—or a man? In time of trouble the answer becomes clear: mankind is formless clay; his spirit he derives from his heroes, from his traditions, from well‐accepted thoughts and ways of life, from storied legends, and from firmly held standards of value. To hold high Denmark's values Bohr and other leaders created and disseminated at their peril a great book entitledDanish Culture. Warned of a plot to seize him, Bohr had to flee for his life in a small boat across open waters to Sweden in November 1943, but the work went on and Danish resistance stood fast another year and a half.

ISSN:0031-9228    

DOI:10.1063/1.3050711

出版商:AIP    

年代:1963

数据来源: AIP

摘要:

The linear accelerator was invented very early in the history of particle accelerators, but it has been one of the latest accelerators to be exploited. This is principally because of the very large quantities of radio‐frequency power required to attain respectable energies in a reasonable distance. Radar developments during World War II resulted in production of the necessary megawatt oscillators or amplifiers, and linear accelerators, both for electrons and positive ions, are now operating in several centers. The electron linear accelerator has been extended to billion‐volt energies, and in the Stanford two‐mile version it will soon set new energy records between 20 and 40 BeV. The proton linear accelerator has had a less spectacular history. The highest energy yet achieved in a proton linac is about 70 MeV (at the University of Minnesota). Smaller proton linacs are in use as injectors for proton synchrotrons, but no machine has been built or is under construction for the range above 100 MeV. This is because synchrocyclotrons for this energy range are much cheaper and have been preferred for this reason, in spite of the fact that the beam from a synchrocyclotron cannot be nearly as intense or as well collimated as the beam from a linear accelerator.

ISSN:0031-9228    

DOI:10.1063/1.3050712

出版商:AIP    

年代:1963

数据来源: AIP

摘要:

The IAEA‐UNESCO Symposium on Inelastic Scattering of Neutrons in Solids and Liquids held September 10–14, 1962, at Chalk River, Ont., was the third international symposium since 1957 in this rapidly developing field. At the first meeting held in September 1957 in Stockholm, 11 papers from 6 countries were presented, whereas at the meeting just concluded, the program was limited to 65 papers from 13 countries. This growth reflects both the greater recognition by the physics community of this powerful experimental technique and the greater availability of nuclear machines to provide the neutron sources needed for measurements.

ISSN:0031-9228    

DOI:10.1063/1.3050713

出版商:AIP    

年代:1963

数据来源: AIP

摘要:

In 1931, while he was a research instructor in chemistry at Brown University, Lars Onsager published two papers on the theory of reciprocal relations for irreversible processes, and thereby laid the foundations for the now flourishing subject of irreversible thermodynamics. As a most fitting recognition of the thirtieth anniversary of this achievement, Brown University played host, this past June, to an International Conference on Irreversible Thermodynamics and the Statistical Mechanics of Phase Transitions (sponsored by the International Union of Pure and Applied Physics, the National Science Foundation, and the Air Force Office of Scientific Research). The conference began with a suitably impressive ceremonial session at which President Barnaby Keney of Brown conferred the University's honorary degree of Doctor of Science upon Onsager, who is now J. Willard Gibbs Professor at Yale.

ISSN:0031-9228    

DOI:10.1063/1.3050714

出版商:AIP    

年代:1963

数据来源: AIP

摘要:

A small topical conference on transport theory took place on September 13, 14, and 15, 1962, at the Little Harbor Farm, Woods Hole, Mass. The conference was sponsored by the National Academy of Sciences and the Air Force Office of Scientific Research. Its broad aims were to bring together researchers in the various fields related to transport theory, and to discuss common interdisciplinary areas of research as well as problem areas more specific to a given area of research.

ISSN:0031-9228    

DOI:10.1063/1.3050715

出版商:AIP    

年代:1963

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.3050716

出版商:AIP    

年代:1963

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.3050719

出版商:AIP    

年代:1963

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.3050720

出版商:AIP    

年代:1963

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.3050721

出版商:AIP    

年代:1963

数据来源: AIP