Einstein endorsed the view of Kaluza that gravity could be combined with electromagnetism if the dimensionality of the world is extended from 4 to 5. Klein appl

"The standard treatise on the general theory of relativity." — Nature "Whatever the future may bring, Professor Weyl's book will remain a classic of physics."

'For those interested, the book is a good and well-written overview of the work of Wesson and his collaborators. For those with a general interest in extensions

Space, Time, Matter, and Form collects ten of David Bostock's essays on themes from Aristotle's Physics, four of them published here for the first time. The fir