PROBLEM OF SCIENCE.

New Zealand Herald, Volume LXIX, Issue 21160, 18 April 1932, Page 11

PROBLEM OF SCIENCE.

NATURE OF COSMIC RAYS.

PROFESSOR COMPTON'S VISIT. A DISTINGUISHED SCHOLAR. A visitor of distinction in the scientific world who arrived at Auckland by the Aorangi yesterday is Professor A. H. Compton, who has been professor of physics at the University of Chicago for the past nine years. During his comparatively short career Professor Compton has received honours from universities in all parts of tho United States, from Britain, Belgium, Italy and India. He was awarded tho gold medal of the American Academy of Sciences in 1926, the Nobel prize in physics in 1927 and the gold medal of the American Radiological Society in 1928. Professor Compton is at present conducting world-wide investigations regarding the intensity of the cosmic rays and is visiting New Zealand as the head of one of seven expeditions that he has organised to collect data in different parts of the world. Ho will proceed to the Hermitage, Mount Cook, accompanied by several New Zealand scientists, there to take observations at as high a level as possible on Mount Cook and also on lower levels for purposes of comparison. The whole work is being carried out under the auspices of tho University of Chicago and the Carnegie Institution. Professor Compton's own expedition to New Zealand is the most extensive of the seven. Tho other six are one to India and Ceylon, Singapore, Java and Cashmere; one to Capetown and other parts of South Africa; one to the southern parts of South America; one to Alaska and tho western United States; one to Baffin Bay, in the north polar regions; and one to Spitzbergen and other parts of Europe. Observations are required to be made as near as possible to the poles and at the equator. Rival Theories. " It is not yet known whether these cosmic rays are similar to X-rays or are electrical in character," said Professor Compton yesterday. "If they are of the latter type we should expect them to be more intense near the magnetic poles and less intense near the magnetic equator. It so happens that southern New Zealand is as close to the south magnetic pole as one could conveniently get, and that is the reason for coming here. " From earlier experiments it is known that there are no large variations in the intensity of the cosmic rays over different portions of the earth. Some experimenters have noted small though definite differences, while others have claimed that no differences exist. No really thorough geographic survey has heretofore been made. " It is possible that these rays may como from the upper portions of the earth's atmosphere. In this case climatic differences such as the differences to be found in oceanic areas as compared with Continental areas may be of importance. It is hoped that the results of the measurements in New Zealand. taken together with those in other localities now being made, may help us to decide whether these rays are coming from the earth's atmosphere or beyond and what the nature of the rays is." Question of Philosophy.

On the broad problem of whether the universe is gradually disintegrating or whether it has within itself the principle of continual re-establishment, Professor C'ompton has taken no side. " I have felt," he says, " that the information we have now available may bo equally well interpreted according to the theory of Millikan or the theory of Jeans; and I doubt if the information which we get will enable us to distinguish between the two theories. I think the "decision between the two lies rather with philosophy than with science."

It is anticipated that five of the expeditions will have completed their work in about five months. The north polar one and the one to the south of South America will take longer, but they should be completed by the end of the year. Professor Compton is to spend a few days in Auckland before going south, and will lecture on the cosmic rays at the University College this evening. He has already made measurements on board ship crossing the equator and at Hawaii. After completing his work at Mount Cook he will go to Sydney and make further observations at Mount Kosciusko. From there he will return by way of Wellington to Peru to obtain further measurements there and in Mexico.