On Gravitation and Relativity: being the Halley Lecture delivered on June 12, 1920

Abstract

THERE is a special appropriateness, as Prof. Sampson points out, in choosing a gravitational subject for the Halley Lecture, in view of the important part that Halley played in securing the publication of the “Principia.” The lecture is an able résumé of the various speculations on the subject, from Galileo's “Dialogues” and Newton's hypothesis of æther-pressure down to Einstein's theory. The author evinces the highest admiration for Einstein's skill in devising a formula which expresses his results “without redundancy, defect, or effort, and whose boldness, range, brilliance, and resounding successes” have commanded universal attention; but on proceeding to examine the formula in detail he confesses to his dislike of some of the devices employed, in particular imaginary time and the obliteration of the distinction between past and future. He alludes to Newton's experiment of the rotating bucket and to Foucault's pendulum experiment as establishing the possibility of detecting the absolute direction of an axis of rotation. It will probably be admitted, even by the convinced relativist, that it is of advantage to students to have the claims of the older “common-sense” kinematics placed before them in an attractive form, which the author has certainly done. On Gravitation and Relativity: being the Halley Lecture delivered on June 12, 1920. Prof. R. A. Sampson By. Pp. 24. (Oxford: At the Clarendon Press, 1920.) Price 2s. net.