LAW OF LIGHT.

Star (Christchurch), Issue 19812, 2 December 1919, Page 8

LAW OF LIGHT.

«. THE NEW THEORY. By Telejyrapli—Press Agfocintion—Copyright " Th« Time! " Sorvico. (Received December 2, 12.40 p.m.) LONDON, November 2S. Professor Einstein, in concluding an abstruse article in " The Times," itay« that the comment is calculated to cheer up the devoted Newtonians, whose confidence wan recently shaken. Whilo the basic of the new theory of gravitation diverged from Newton's, in practical application, they agree so closely that it in difficult to find cases in which the actual differences could be subjected to observation. Newton's clear and wide ideals for ever retain their significance, as the foundation on which our modern conceptions of physics are built. "Tho Times," in an editorial, says tint the new con.option makes Httlo diffcreneo to tho practical world. The laws of physics inivo becomo much complicated hut we may measure out land -lid believe our clocks as we did before the emergence of Professor Einstein. (A remarkable discusuon took place before the Royal Society eaily in November on the results of observations of the total solar eclipse on May 20 at Principe (West Africa) and Brazil. Sir Frank Dyson, the Astronomer Royal, who convinced the mating by photographs of the stare, demonstrated the accuracy of the theory put forward by the Swiss physicist, I>r Einstein, that light, like matter, was subject to tho law 3of gravity. Sir Joseph Thomson, formerly professor of physics at tho Royal Insukition, London, and now of_ Trinity College, Cambridge, in summing up the discussion declared that :i whole continent of the most important t.ew scientific ideas relating to physio bad been discovered. It. was tho jrre.ii.ost discovery conncciod wit-n gravitation r-iiicu Newton, ;iivl one of the E."e--;to3t achievements in the history of minimi thougiit.j The Australian Government astronomer (Dr J. M. Baldwin) supplies the following iniormntion:— "The results announced at this meeting of the Royal Society have been anxiouslv awaited by the scientific world. Two British expeditions were sent out to observe the total solar eclipse of Mav 29, the one, consisting of Proicssor fedington and Mr Oottm'gham, going to Principe, an island off the west coast of Africa, the other, consisting of Dr Crommelin and Mr Davidson, going to Sobral, in Brazil. Both expeditions had one object in view, to determine if a ray «f light is bent when it posses near a massive _ body. This eclipse ofFered exceptional opportunities of testing if any such effect exists, for the duration ol eclipse was considerable (about hvo. minutes at each ot th« stations selcaed), so that several photographs could be taken dining totalitv. and there were about thirteen stars in the neigh, bourhood of the eclipsed sun sutticieniiv bright to appear on the photor . .lis bo favourable an opportunity will not occur again for verv manv vears. There were tliree possibilities to look for—- (.) no displacement, which would mean that light was not acted on hv gravitv: (2) a displacement of 0.87500 of aV'or light grazing the sun, showing that light was acted on bv gravitv. 0 r in other words has A-.eidit; (3) ment of l.,4sev of .re for light era/.mg the sun. which is the displacement deduced from Kin -tern's theorv of "ravitauori It is in all.probability-' the plates from bobral that have now been measured, and lmro given a satisfactory answer to the question of the amount ot deflection ot' Ikrht produced in a gravitational fi hi, and have shown that, bis deflection i< cuiml to that predicted by hinstcin's theory.