Einstein’s Universe: the layperson’s guide – Nigel Calder ****
Einstein’s Universe is a short and useful book which outlines special and general relativity, and how Einstein’s framework for understanding space and time has remained intact and been continually confirmed since he first gave it to us.
This would be a good start for anyone knowing very little about relativity. Nigel Calder goes through the main aspects and predictions of the special and general theories in short, readable sections, and at the beginning of each chapter there are a few helpful sentences that state plainly what’s going to be talked about. The only equation in the book is E = mc2, and the explanation of the origin of this is better than in most places. The section on how gravity affects time is particularly good for those new to the concept.
The book was originally written in 1979 and, apart from a new afterword, everything remains the same in the 2005 edition now available. This is not really a problem, however, for a book which explains the basics of its subject that are still valid. And having understood these basics, readers would be in a good position to go on to something slightly more technical, like Russell Stannard’s Relativity: A Very Short Introduction or Bruce Bassett’s Introducing Relativity.