Einstein was not isolated or outsider genius. He was a young physicist who didn't get academic position. Einstein's best friend Marcel Grossmann was a mathemat

Einstein was not isolated or outsider genius. He was a young physicist who didn't get academic position. Einstein's best friend Marcel Grossmann was a mathematician specializing in differential geometry and tensor calculus. Those were exactly the tools he needed for his breakthrough. Grossmann was important facilitator for Einstein. There were others. "Olympia Academy" and his wife for example.