Word: fission
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Dates: during 1950-1959
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...announcement that he had ordered development of the hydrogen bomb was a decision that most U.S. citizens obviously approved, but about which none could be happy; driven by inexorable forces, the U.S. was setting out to make a weapon that would pale the deadliness of the atomic-fission bomb (see SCIENCE). As events had turned, it was essentially a defensive measure. The Russians could build and doubtless were building their own hydrogen bomb. If undeterred by threat of retaliation in kind, the Russians could deliver it by aircraft almost anywhere in the U.S.; by submarine, or in a sneak attack...
...most of the U.S. public the hydrogen bomb was still a direful novelty last week, but to scientists there was little new about it. Long before the discovery of uranium fission they had known that familiar, plentiful hydrogen could make prime nuclear fuel. They had even demonstrated on a laboratory scale some of its nuclear reactions. They could not make the process work practically, but whenever they felt discouraged, they looked up at the shining sun whose radiation, derived from hydrogen, is the vital force of the world...
...Fission v. Fusion. The new-style "fusion" of hydrogen and the old-style "fission" of uranium have a family resemblance. Both depend on the odd and unexplained fact that atomic nuclei do not weigh as much as the sum of the individual nucleons (protons and neutrons) which they contain. It is as if a dozen apples in a paper bag did not weigh as much as the same apples spilled out on the kitchen table and weighed separately...
...Uranium fission works by dividing large "bushel basket" nuclei. When a uranium nucleus splits in two, forming two smaller nuclei such as krypton and barium, the weight of all fragments added together is less than that of the original uranium. The weight-loss turns into free energy...
...only two commands: yes or no-i.e., an electrical signal or no signal. So all information fed into the machines has to be predigested into yes-or-no binary arithmetic. Any number, however large, can be expressed in this form. So can elaborate equations like those from the fission problem done for Princeton by the I.B.M. machine. Even languages can be translated in binary numbers. (One way: making different numbers stand for each character, syllable or word.) Any sort of information, once the mathematicians go to work on it, can be broken down into...