SIDELIGHTS ON RELATIVITY

By Albert Einstein

Contents

ETHER AND THE THEORY OF RELATIVITY

An Address delivered on May 5th, 1920, in the University of Leyden

GEOMETRY AND EXPERIENCE

An expanded form of an Address to the Prussian Academy of Sciences
in Berlin on January 27th, 1921.





ETHER AND THE THEORY OF RELATIVITY

An Address delivered on May 5th, 1920, in the University of Leyden



How does it come about that alongside of the idea of ponderable
matter, which is derived by abstraction from everyday life, the
physicists set the idea of the existence of another kind of matter,
the ether? The explanation is probably to be sought in those phenomena
which have given rise to the theory of action at a distance, and