e wrote 11 scientific works, 5 of which were on radiation mathematics and on the quantum theory of solids.
In July 1912, he returned to Switzerland and the ETH Zürich, where he taught about analytical mechanics and thermodynamics until 1914. During his time at the ETH Zürich, he also studied continuum mechanics, andthe molecular theory of heat and the problem of gravitation. In 1914, he returned to Germany and was appointed director of the Kaiser Wilhelm Institute for Physics (1914–1932) and a professor at the Humboldt University of Berlin.
He soon became a member of the Prussian Academy of Sciences, and from 1916 to 1918 he served as president of the German Physical Society. In 1920, he became Foreign Member of the Royal Netherlands Academy of Arts and Sciences, and was elected a Foreign Member of the Royal Society (ForMemRS) in 1921.
In 1933, Einstein visited the United States for the third time. But unlike previous visits – where he conducted lecture series and tours – on this occasion he knew he could not return to Germany, due to the rise of Nazism under Adolf Hitler. After performing his third two month visiting professorship at American universities, he and wife Elsa traveled to Antwerp, Belgium in March of 1933.
Upon their arrival, when they learned that their cottage had been raided by the Nazis and their personal sailboat confiscated, Einstein renounced his German citizenship. A month later, Einstein’s works were among those targeted by Nazi book burnings, and he was placed on a list of “enemies of the German regime”, with a bounty of $5000 on his head.
During this period, Einstein became part of a large community of German and Jewish ex-patriots in Belgium, many of whom were scientists. For the first few months, he rented a house in De Haan, Belgium, where he lived and worked. He also dedicated himself to helping Jewish scientists escape persecution and murder at the hands of the Nazis.
In July 1933, he went to England at the personal invitation of his friend and naval officer Commander Oliver Locker-Lampson. While there, he met with then-Member of Parliament Winston Churchill and former Prime Minister Lloyd George, and asked them to help bring Jewish scientists out of Germany. According to one historian, Churchill dispatched physicist Frederick Lindemann to Germany to seek out Jewish scientists and place them in British universities.
Einstein later contacted leaders of other nations, including Turkish Prime Minister Ismet Inönü to ask for help resettling of Jewish citizens fleeing the Nazis. In September 1933, he wrote to Inönü, requesting the placement of unemployed German-Jewish scientists. As a result of Einstein’s letter, Jewish invitees to Turkey eventually totaled over 1,000 individuals.
Though Locker-Lamspon urged Britain’s parliament to extend citizenship to Einstein, his efforts failed, and Einstein accepted an earlier offer from the Princeton Institute for Advanced Study in New Jersey to become a resident scholar. In October 1933, Einstein arrived in the U.S. and took up the position.
At the time, most American universities had minimal or no Jewish faculty or students due to quotas that limited the number of Jews that could enroll or teach. These would expire by 1940, but remained a barrier for American-Jewish scientists to participate fully in academic life and receive a university education.
In 1935, Einstein applied for permanent citizenship in the US, which he was granted in 1940. He would remain in the US and maintain his affiliation with the Institute for Advanced Study until his death in 1955. During this period, Einstein tried to develop a unified field theory and to refute the accepted interpretation of quantum physics, both unsuccessfully.
The Manhattan Project:
During World War II, Einstein played an important role in the creation of The Manhattan Projectthe – development of the atomic bomb. This project began after Einstein was approached by a group of scientists led by Hungarian physicist Leó Szilárd in 1939. After hearing their warnings of a Nazi nuclear weapons program, he co-wrote a 