A handwritten letter by the Jewish-German physicist Albert Einstein which includes complex details of evidence regarding his efforts to discover the Theory of Everything has been revealed. The letter will be put up for auction next week at the Kedem Auction House in Jerusalem at a starting price of $20,000.

Einstein sent the letter in 1950 to his friend, former assistant and colleague, the mathematician Ernst Gabor Strauss, in response to Strauss's critiques of his unified field theory. Einstein concluded that space and time are one at the beginning of his career and spent the next decades developed a unified field theory which would consolidate the fundamental laws governing nature - gravity and electromagnetic power - into a single theoretical framework.

"I am glad that you are working so hard on the question of compatibility," Einstein wrote in German to Strauss. "But I do not think your concerns are justified. I would like to formulate the proof so that your letters are taken into account."

Einstein then continued a lengthy scientific explanation, or proof for Strauss, interpreting Strauss’ equations and solutions to distinguish real degrees of freedom from coordinate effects in order to understand the meaning of the equations’ solutions.

Although Einstein devoted the last 30 years of his life to developing the unified field theory, he was ultimately unsuccessful in forming the Theory of Everything. However, his efforts prompted other scholars to search for such a theory and his research in the field is one of his most important contributions to the world of science.

Strauss was Einstein's assistant at the Princeton Institute for Advanced Research from 1944-1948, formulating mathematical models for Einstein's ideas and working alongside him on united field theory. The two published three papers together.

Strauss, especially remembered for his contribution to the development of "Ramsey Theory," was born in Munich to a Jewish Zionist family. In 1933, he fled with his family to the British mandate of Palestine. After a brief period of study at the Hebrew University, he emigrated to the United States and completed his studies at Columbia University. In the course of his career, he worked with some of the most prominent mathematicians of his era, including Paul Erdesh and Richard Bellman.

"The letter is a historical item of extraordinary value that has made its way to us," said Meron Eren, co-owner of the Kedem auction house. "Albert Einstein is considered by many to be the leading physicist of the 20th century. His theory of relativity was initially met with great skepticism in the scientific world but was eventually accepted, making Einstein famous. This letter deals with the unified field theory, an incomplete theory. However, Einstein's contribution to science in this field is one of the most important in the field of science."