Erwin Freundlich (1885-1964) was a renowned astronomer and close working associate of Albert Einstein. In this 1920 translation Freundlich provides a concise explanation of the ideas and theories which led to the general theory of relativity. The text is also notable for containing a preface written by Einstein himself.
In this 1920 translation Erwin Freundlich explains the ideas and theories which led to the general theory of relativity.