Berlin, war, marriage breakup, and general relativity completed (1914–1915)

Abstract Einstein arrived in Berlin in March 1914 and began to integrate himself into its scientific and cultural activities. Mileva and the children arrive, and Einstein moved in with them at the end of May. Ehrenfest visited.

Einstein became more and more absent from home. By mid-July Mileva had left for the home of Haber, who mediated between Mileva and Einstein. Einstein was prepared to live with Mileva only if she became a sort of housekeeper, as he detailed in a startling letter.

The couple agreed to separate and Besso escorted them back to Zurich at the end of July. The outbreak of the First World War stranded Freundlich in Russia as he waited for a solar eclipse. Trench warfare began.

Einstein began some experimental work with van der Haas on atomic magnetism. Restrictions on travel made it difficult for Einstein to visit his sons. The British blockade began to lead to food shortages.

Einstein realised that the Entwurf theory was incorrect and embarked on exhaustive work to replace it. He was worried that he would be beaten to the correct theory by Hilbert. In a series of presentations in November, he showed that the new theory could successfully explain the orbit of Mercury.

General relativity was born.