Word: decays
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Dates: during 1960-1969
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...unchallenged constants that have become the bench marks of basic research. Among them are absolute zero, which represents cold so intense that there is no molecular movement, and the speed of light, which was written into Einstein's age-shaking equation, E = mc2. Constant too is the decay of radioactive materials at rates that cannot be altered by heat, cold, pressure, magnetism, or any other influence.*Such reliability means that ancient tombs can be dated by the decay of carbon 14; the age of the earth's most ancient rocks may be measured by decaying uranium...
...constants can indeed be changed-however small the alteration-is always big news in science. And last week physicists at Westinghouse Research labs in Pittsburgh announced that they had turned the trick. Working with a radioactive substance, iron 57, they proved that they could influence the rate of radioactive decay...
Iron 57 exists in both an "excited" (radioactive) and an "unexcited" state. It decays from one to the other with the emission of gamma rays. When an F 57 atom in the unexcited state ab sorbs a gamma ray, it too becomes excited, then decays to the unexcited state again a brief instant later. Westinghouse's physicists surrounded excited F 57 atoms with a blanket of the same atoms in the unexcited state and recorded their behavior. As the excited atoms began to decay at the normal rate, some of the gamma rays they emitted were absorbed by unexcited...
...marginal exception: beryllium 7, with a decay rate that changes by at most 0.1% when its atoms are built into certain chemical compounds...
...next 40 years we must rebuild the entire urban United States. It is harder and harder to live the good life in American cities. There is the decay of the centers and the despoiling of the suburbs. There is not enough housing for our people or transportation for our traffic. Open land is vanishing and old landmarks are violated. Worst of all, expansion is eroding the precious and time-honored values of community with neighbors and communion with nature. Our society will never be great until our cities are great...