Word: fusion
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...Fusion" of light elements, on which the hydrogen bomb depends, is the senior source of nuclear energy. More than 20 years ago, at Cambridge University, Physicists John D. Cockcroft and Ernest T. S. Walton shot hydrogen nuclei (protons) from a primitive high-voltage machine at a lithium target. A few of the protons hit lithium nuclei. The product of each such reaction: two atoms of helium and 17.3 million electron-volts of energy...
...scientists, however, did not forget fusion. Graven on their minds was a curious set of facts: when the elements are arranged in series according to their atomic weights, the atoms of those in the center of the series are lighter than they "should be." So when an atom of uranium (the heaviest natural element) splits into two fragments and a few loose neutrons, all the pieces, added together, weigh less than the original uranium atom. By Einstein's famous equation (E = Mc2), this loss of weight shows up as the energy that powers uranium bombs...
This was an exciting and ominous prospect, but the trouble with fusion reactions is that they are not self-starting; uranium fission is. When a sufficient amount (critical mass) of U-235 is assembled, a single, slow-moving neutron can start an atom-splitting chain reaction in it and make the whole chunck explode. Light elements are not so accommodating. Their atoms must be slammed together violently to make them group into larger atoms and yield energy...
...slightly bigger (319.1 sq. mi.), but Cole hinted strongly that hydrogen bombs have grown much better since 1952, and that still more improvement is in prospect. "The 1952 tests," he said, "did not mark the end of the line in hydrogen research. Terrible secrets still lie undiscovered in the fusion of nuclei. In due course, we can be sure, the ingenuity of man will ferret out these secrets...
...skip over lightly.* Although a Roman Catholic himself, Dawson does not take the tack of the conventional Catholic medieval apologist, who regards the period as a happy but vanished Golden Age when there were no Protestants around. For Historian Dawson, the Middle Ages can be studied only as a fusion of religion and culture, a "long 1,000-year process" that formed Western culture and continues to influence...