Einstein, Albert - Relativity. The Special & General Theory. A Popular Exposition... Authorised Translation by Robert - 1920

1920. The listing says 'third edition'; today one would more likely refer to it as the 'third printing' of the first edition, also from 1920. Frontispiece portrait of Einstein, illustrated (formulas & graphs), size 12.5 x 20 cm, with various appendices, including bibliography & index; cloth-bound, no dust jacket. Excellent condition, flyleaves discolored, interior in very good condition, only a single rust spot, name on the verso of the front free endpaper, interior printed on heavy paper.

This book, which Albert Einstein (1879-1955) published in 1920, provides a popular explanation of his theories, without much mathematics. It covers special relativity (1905) and general relativity. Relativity is one of the two pillars of modern physics (alongside quantum mechanics). His work has had and continues to have the influence on the philosophy of science. To the general public, he is mainly known for his formula for the equivalence of mass and energy, E = mc². This formula is roughly called "the most famous equation in the world." He received the Nobel Prize in Physics in 1921 "for his contributions to theoretical physics, and in particular for his discovery of the law of the photoelectric effect," a crucial step in the development of quantum theory.