Space and Time, in Contemporary Physics, an Introduction to the Theory of Gravitation (Classic Reprint)

Excerpt from Space and Time, in Contemporary Physics, an Introduction to the Theory of Gravitation<br><br>Probably no physical theory in recent times has given rise to more discussion amongst philosophers than the principle of relativity. One school of thought agrees that physicists may well be led to recast their notions of space and time in the light of experimental results. Another school, however, is of opinion that these questions are no concern of the physicists, who should make their theories fit the philosophers' conceptions of these fundamental units.<br><br>The theory of relativity consists of two parts, the old special theory, and the more recent general theory.<br><br>The main philosophic achievement of the special theory of relativity is probably the recognition that the description of an event, which is admittedly only perfect if both the space and time co-ordinates are specified, will vary according to the relative motion of the observer; that it is impossible to say, for instance, whether the interval separating two events is so many centimetres and so many seconds, but that this interval may be split up into length and time in different ways, which depend upon the observer who is describing it.<br><br>The reasons which force this conclusion upon the physicist may be made clear by considering what will be the impression of two observers passing one another who send out a flash of light at the moment at which they are close together. The light spreads out in a spherical shell, and it might seem obvious, since the observers are moving relatively to one another, that they cannot both remain at the centre of this shell.<br><br>About the Publisher<br><br>Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com<br><br>This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.