نظرية ثابت الزمن ومتغير الطاقة

In 1938 many people feared that Hitler would build an atomic bomb after word spread that German scientist had split the uranium atom (fission). However, one of Hitlers mistakes was his persecution of Jewish scientists. This persecution resulted in numerous scientists seeking asylum in the United States. One such scientist was Albert Einstein. Einstein, abandoning his belief in pacifism, urged then president Franklin Roosevelt to develop an atomic bomb before Hitler did. Eventually Roosevelt agreed and the United States attempt at building the atomic bomb was codenamed The Manhattan Project.
The Manhattan Project was carried out in extreme secrecy. By 1945, the project had nearly 40 labratories and factories which empolyed approximately 200,000 people. Among these employees were some of the greatest scientist that have ever lived. Included in this lot were Albert Einstein, Enrico Fermi, Richard Feynman, J. Robert Openheimer, and Harold Urey (and this is but a hand full of the many).1