Physicists Leo Szilard and Edward Teller reached out to Albert Einstein, who signed a letter warning President Roosevelt about the German nuclear threat, initiating the Manhattan Project.
The event in question is b) Albert Einstein and Leo Szilard writing a letter to Franklin Roosevelt. In 1939, fearing the development of an atomic bomb by Nazi Germany, physicists Leo Szilard and Edward Teller reached out to Albert Einstein, who signed a letter warning President Roosevelt about the German nuclear threat. This event led to the initiation of the Manhattan Project, a program aimed at creating nuclear weapons.
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