Letters written by Albert Einstein to his family have shed light on the scientist's personal life, including a string of extramarital affairs.
The letters reveal personal details of the scientist's life
The German-born scientist travelled extensively and wrote hundreds of letters to his family.
The letters were released by the Hebrew University of Jerusalem which had held the collection for many years.
Einstein's stepdaughter, Margot, had stated in her will they should not be revealed until 20 years after she died.
Einstein is known to have had a dozen lovers, two of whom he married, said Barbara Wolff of the Hebrew University's Albert Einstein Archives.
The 3,500 pages of correspondence include letters to his first and second wives and children between the years 1912-1955.
Einstein wrote almost daily to his second wife Elsa and her daughter Margot in that period.
He openly discussed his affairs, saying that women showered him with "unwanted" attention.
In one 1931 letter to Margot, Einstein complains about one of his conquests, a Berlin socialite: "Mrs M" - Ethel Michanowski - "followed me [to England], and her chasing me is getting out of control.
"Out of all the dames, I am in fact attached only to Mrs L, who is absolutely harmless and decent."
In another letter to Margot, he asks her to pass on "a little letter for Margarita [known as his 'Russian spy lover'], to avoid providing curious eyes with titbits."
The letters deal with a number of other topics:
- His Nobel Prize money:
Despite reports that Einstein transferred the Nobel Prize money directly to Switzerland following a divorce agreement in which it was assigned to his first wife, Mileva, the letters reveal he instead invested the major part of it in the US, where he settled after being driven out of Nazi Germany. Much of the money was later lost in the Depression.
- His son:
Einstein found his son Eduard's schizophrenia difficult to accept, and often expresses the idea that it would have been better if Eduard had not been born.
- His stepdaughter:
In a letter to Elsa in 1924, Einstein writes: "I love her [Margot] as much as if she were my own daughter, perhaps even more so, since who knows what kind of brat she would have become [had I fathered her].''
In a letter to Elsa in 1921, he says: "Soon I'll be fed up with the relativity. Even such a thing fades away when one is too involved with it."