Manhattan Project:
During World War II, Einstein had concerns about Nazi Germany potentially developing atomic weapons. In 1939, he and other physicists, including Leo Szilard, wrote the Einstein-Szilard letter to President Franklin D. Roosevelt, warning about the potential danger. This letter is often considered to have played a role in prompting the United States to initiate the Manhattan Project, which ultimately led to the development and use of the atomic bomb.
Institute for Advanced Study:
After the war, Einstein accepted a position at the Institute for Advanced Study in Princeton, New Jersey. He spent the last years of his life there, continuing his research and contributing to the intellectual atmosphere of the institute.
Influence on US Science and Technology:
Einstein's scientific work and theories had a profound impact on scientific research and development in the United States. His contributions advanced the fields of physics, astronomy, and cosmology, influencing numerous scientific disciplines and technological innovations.
American Citizenship:
Einstein became an American citizen in 1940, renouncing his German citizenship in the process. Although his primary scientific contributions took place in Europe, his later years were spent in the United States, influencing the scientific community there.