The Special Theory of Relativity: Based on a short course of lectures delivered in the late 1930s this short book presents the theory of Special Relativity by formulating a redefinition of the measurement of length and thus will appeal to students of physics who wish to think through Einsteinâs thought without the encumbrance of quasi-scientific concepts and language. Relativity: A Very Elementary Exposition: This brief lecture delivered in October 1921 and published for the first time in 1925 offers an explanation of Einsteinâs theory of Special Relativity for the non-scientist giving a general overview that does justice both to the actual physics involved and the wider implications of this revolutionary discovery of the 20th century. . Language: English