**“Shaken to its depths by the tragic catastrophe in Palestine, Jewry must now show that it is truly equal to the great task it has undertaken. It goes without saying that our devotion to the cause and our determination to continue the work of peaceful construction will not be weakened in the slightest by any such set-back. But what has to be done to obviate any possibility of a recurrence of such horrors?**

**The first and most important necessity is the creation of a modus vivendi with the Arab people”.**

**Albert Einstein, August 1929. **(here)

Einstein attends a concert with Helen Dukas at the Great Synagogue in Berlin, 1930.

On December 10, 1915 Einstein told his best friend Michele Besso that his wildest dreams have now come true: general covariance and the perihelion of Mercury. Einstein wished Besso best regards and signed “your satisfied kaput Albert”.

Sometime in October 1915 Einstein dropped his old Einstein-Grossman theory, but he realized that the key to the solution lies in his 1914 review article “The Formal Foundation of the General Theory of Relativity”. He was finally led to general covariance. Starting on November 4 1915, Einstein gradually expanded the range of the covariance of his field equations.

Between November 4 and November 11, 1915, Einstein simplified the field equations, and was able to write them in general covariant form in an addendum to the November 4 paper, published on November 11. But there still remained difficulties.

On Thursday, November 18, Einstein presented to the Prussian Academy his solution to the longstanding problem of the precession of the perihelion of Mercury, on the basis of his November 11 general theory of relativity. **Today, exactly one year from now the world will celebrate one hundred years to this achievement. Mazal Tov.**

Between November 18 and November 25 Einstein found that he could write the field equations with an additional term on the right hand side of the field equations involving the trace of the energy-momentum tensor, which now need not vanish. Hence, Einstein resolved the final difficulties of his November 11 1915 theory of gravitation in his final November 25 1915 paper. These were the November 25 1915 field equations.

How did Einstein do this? Read my two papers (one and two) and see how Einstein solved the problem.

In winter 1916 Einstein exchanged letters with his friend from Leiden Paul Ehrenfest and rederived the November 25, 1915 field equations. How did Einstein do this? Read my two papers (one and two) and find out.

Einstein elaborated his 1912 Disk thought experiment, and his 1914 thought experiment, originally suggested by Newton in the *Principia*, the Two Globes thought experiment. After presenting the 1905 magnet and conductor thought experiment, Einstein wrote, “Examples of this sort … lead to the conjecture that the phenomena of electrodynamics as well as those of mechanics possess no properties corresponding to the idea of absolute rest”. The globes thought experiment was intended to demonstrate that this could be extended to accelerated motions and to the theory of gravitation using Mach’s principle (still not defined as a principle).