German-born theoretical physicist widely considered one of the greatest physicists of all time. While best known for the theory of relativity (and specifically mass-energy equivalence, E=mc2), he was awarded the 1921 Nobel Prize in Physics for his 1905 explanation of the photoelectric effect and “for his services to Theoretical Physics.” Crisp and precise ink signature, “A. Einstein,” on an off-white 4.25 x 2 slip. In fine condition, with a vertical fold through a single letter of signature. Auction LOA John Reznikoff/PSA/DNA and R&R COA.
