ISSN:0031-9228    

DOI:10.1063/1.2815134

出版商:AIP    

年代:1986

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.2815135

出版商:AIP    

年代:1986

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.2815136

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

The first color photographs ever to grace the pages ofPhysical Review Lettersshow us the fluorescent glow from some 500 sodium atoms caught in the first successfully demonstrated optical trap for neutral atoms. The 21 JulyLetterby Steven Chu, John Bjorkholm, Arthur Ashkin and Alex Cable at Bell Labs, reports that this tiny “optical dipole” trap, formed at the focus of a single laser beam, was able to hold onto an ultracold, high‐density accumulation of atoms for several seconds and manipulate them in space. In recent days the group has been able to hold a much larger collection of sodium atoms for a fraction of a minute with a newer optical‐trap design.

ISSN:0031-9228    

DOI:10.1063/1.2815137

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

The University of Washington group that made its reputation by doing measurements of exquisite precision on single protons, electrons and positrons held for astonishingly long times in a Penning trap (PHYSICS TODAY, May 1985, page 17) has finally succeeded in trapping antiprotons. They accomplished this feat in July at the LEAR low‐energy antiproton ring at CERN, where they had been granted one day's running to do a feasibility test for precision antiproton measurements they hope to carry out next year.

ISSN:0031-9228    

DOI:10.1063/1.2815138

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

For millennia we have based our views of the universe on observations in the narrow visual octave of the electromagnetic spectrum, 400–800 nm, supplemented during the last half‐century by infrared and radio observations. During the last decade, however, space research has opened the full spectrum, including the entire infrared region and the ultraviolet, x‐ray and &ggr;‐ray regions (see the photo on the cover and figure 1).

ISSN:0031-9228    

DOI:10.1063/1.881039

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

In 1945 the United States emerged from World War II—into a world profoundly altered by scientific growth. Under the pressure of wartime conditions, sophisticated technology—most notably radar—had been developed by exploiting basic physical principles, such as those of electronics and atomic phenomena, and this technology had proved crucial to the war's outcome. Yet in the postwar US, fewer than 25&percent; of high‐school students were studying physics at all, and what physics was taught emphasized rote learning and superficial description. Similar situations existed in the teaching of mathematics and of other sciences.

ISSN:0031-9228    

DOI:10.1063/1.881040

出版商:AIP    

年代:1986

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.2815139

出版商:AIP    

年代:1986

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.2815140

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

Maria Goeppert Mayer is frequently mentioned as an example of a woman who managed to make significant contributions to science in spite of tremendous obstacles. Robert Sachs, Mayer's first graduate student, has given a personal account of her life and career (PHYSICS TODAY, February 1982, page 46). Joan Dash has written a longer biography of Mayer, focusing on her family life. In this article I look at the distinctive character of Mayer's scientific accomplishments. As a mathematical physicist, she worked on a number of apparently unrelated topics during the years 1930–46. I will focus on her work during this period and show how it prepared her for the nuclear physics research for which she received the Nobel Prize in 1963.

ISSN:0031-9228    

DOI:10.1063/1.881041

出版商:AIP    

年代:1986

数据来源: AIP