An extract on #justgoshoot
The discovery and publication in 1987 of an early correspondence between Einstein and Mari revealed that they had had a daughter, called "Lieserl" in their letters, born in early 1902 in Novi Sad where Mari was staying with her parents. Mari returned to Switzerland without the child, whose real name and fate are unknown. Einstein probably never saw his daughter. The contents of his letter to Mari in September 1903 suggest that the girl was either given up for adoption or died of scarlet fever in infancy.
Einstein and Mari married in January 1903. In May 1904, their first son, Hans Albert Einstein, was born in Bern, Switzerland. Their second son, Eduard, was born in Zrich in July 1910. In April 1914 they moved to Berlin. After a few months his wife returned to Zrich with their sons, after learning that Einstein's chief romantic attraction was his first and second cousin Elsa. They divorced on 14 February 1919, having lived apart for five years. Eduard, whom his father called "Tete" (for petit), had a breakdown at about age 20 and was diagnosed with schizophrenia. His mother cared for him and he was also committed to asylums for several periods, finally being committed permanently after her death.
In letters revealed in 2015, Einstein wrote to his early love, Marie Winteler, about his marriage and his still-strong feelings for Marie. In 1910 he wrote to her that "I think of you in heartfelt love every spare minute and am so unhappy as only a man can be" while his wife was pregnant with their second child. Einstein spoke about a "misguided love" and a "missed life" regarding his love for Marie.
Einstein married Elsa Lwenthal in 1919, after having had a personal relationship with her since 1912. She was a first cousin maternally and a second cousin paternally. In 1933, they emigrated to the United States. In 1935, Elsa Einstein was diagnosed with heart and kidney problems; she died in December 1936.
In October 1933 Einstein returned to the U.S. and took up a position at the Institute for Advanced Study, noted for having become a refuge for scientists fleeing Nazi Germany. At the time, most American universities, including Harvard, Princeton and Yale, had minimal or no Jewish faculty or students, as a result of their Jewish quota which lasted until the late 1940s.
Einstein was still undecided on his future. He had offers from several European universities, including Christ Church, Oxford where he stayed for three short periods between May 1931 and June 1933 and was offered a 5-year studentship, but in 1935 he arrived at the decision to remain permanently in the United States and apply for citizenship.
Einstein's affiliation with the Institute for Advanced Study would last until his death in 1955. He was one of the four first selected (two of the others being John von Neumann and Kurt Gdel) at the new Institute, where he soon developed a close friendship with Gdel. The two would take long walks together discussing their work. Bruria Kaufman, his assistant, later became a physicist. During this period, Einstein tried to develop a unified field theory and to refute the accepted interpretation of quantum physics, both unsuccessfully.