ISSN:0002-9505    

DOI:10.1119/1.1970064

出版商:American Association of Physics Teachers    

年代:1964

数据来源: AIP

摘要:

Nuclear fission was discovered twenty five years ago by Hahn and Strassmann. Was the road to the discovery as torturous as some have contended? The roots are examined; the surprising climax and its impact are described. Some scientists have commented on the discovery in retrospect. The discovery of fission is scrutinized both in the light of these comments, and of the general characteristics of scientific discovery.

ISSN:0002-9505    

DOI:10.1119/1.1970067

出版商:American Association of Physics Teachers    

年代:1964

数据来源: AIP

摘要:

A complete translation of the original German article by Hahn and Strassmann on the radio-chemical evidence for fission of uranium has been made. This famous article was first published in January 1939, so that the year 1964 marks its 25th anniversary.

ISSN:0002-9505    

DOI:10.1119/1.1970127

出版商:American Association of Physics Teachers    

年代:1964

数据来源: AIP

摘要:

The Michelson-Morley experiment, performed in Cleveland in 1887, proved to be the definitive test for discarding the Fresnel aether hypothesis which had dominated physics throughout the 19th century. The experiment had been suggested to Michelson by his study of a letter of James Clerk Maxwell, and a preliminary but inconclusive trial had been made at Potsdam in 1881. It seems certain that the experiment would never have been repeated except for the urging of Kelvin and Rayleigh at the time of Kelvin's Baltimore Lectures in 1884, which Michelson and Morley attended. The conclusive null result of the Cleveland experiment was decisive in its influence on Lorentz, FitzGerald, Larmor, Poincaré, and Einstein in developing their theories of the electrodynamics of moving bodies, which culminated in the special theory of relativity. The present account contains material from extensive notes and correspondence related to the work of Michelson and Morley which the writer has assembled during the past years.

ISSN:0002-9505    

DOI:10.1119/1.1970063

出版商:American Association of Physics Teachers    

年代:1964

数据来源: AIP

摘要:

Nordström's scalar theory of gravitation is discussed from a modern point of view, and compared with some aspects of general relativity. We discuss the equations of motion for test masses, the field equations in the presence of matter, and the extent to which the principle of equivalence, Mach's principle, and the expansion of the universe are contained in this model. The theory implies what amounts to a Riemannian metric, and features a positive energy density for the gravitational field.

ISSN:0002-9505    

DOI:10.1119/1.1970068

出版商:American Association of Physics Teachers    

年代:1964

数据来源: AIP

摘要:

The Kramers-Kronig relations are shown by elementary methods to be rigorously valid for linear, causal, stationary systems whose response functions obey simple conditions of boundedness.

ISSN:0002-9505    

DOI:10.1119/1.1970070

出版商:American Association of Physics Teachers    

年代:1964

数据来源: AIP

摘要:

Students of molecular dynamics are often confused by the somewhat arbitrary nature of symmetry coordinates. This paper presents a completely general theory of symmetry coordinates which allows every symmetry coordinate to be obtained for any molecule but which also requires a knowledge of the irreducible representations of the point groups. The moleculesCH3Cl,CH4, andC6H6are used as examples.

ISSN:0002-9505    

DOI:10.1119/1.1970072

出版商:American Association of Physics Teachers    

年代:1964

数据来源: AIP

摘要:

Gravitational redshift of photons from a star and gravitational bending of the path of photons grazing the sun can be derived by using only Newton's laws and the idea of a photon as a particle of masshv/c2. The difference between the relativistic and Newtonian equations for gravitational redshift is too small to be detected and, therefore, gravitational redshift does not provide experimental verification of the general theory of relativity. On the other hand, a Newtonian treatment of gravitational bending of the path of photons gives only half the true amount of total deflection derived by Einstein in 1915 using general relativity. The case of gravitational bending is treated in some detail.

ISSN:0002-9505    

DOI:10.1119/1.1970075

出版商:American Association of Physics Teachers    

年代:1964

数据来源: AIP

摘要:

The history and background of a translation project on a series of eight volumes on lecture demonstrations in physics as given at the University of Moscow and published in the Soviet Union over the last ten years is given. An edited and condensed version of the translation is available on microfilm from the American Institute of Physics for five dollars.

ISSN:0002-9505    

DOI:10.1119/1.1970076

出版商:American Association of Physics Teachers    

年代:1964

数据来源: AIP

ISSN:0002-9505    

DOI:10.1119/1.1970078

出版商:American Association of Physics Teachers    

年代:1964

数据来源: AIP