The MacKaye Theory
Professor James MacKaye of the department of Philosophy recently presented a paper before the American Philosophical Association setting forth a new theory of the universe. Scientists who were present at the meeting and those who have read the MacKaye paper have referred to the work as "epoch-making" and "very important contribution to philosophy and science." There were some who stated their belief that the MacKaye theory will in time become as famous as the Einstein theory. Professor MacKaye has been on the faculty of the College as a visiting lecturer in Philosophy since February, 1925. He has briefly summarized his theory in the following article, which is reeffects, printed from The Dartmouth with Professor MacKaye's permission:
It is a commonplace of physics that the molecules of air in a room at constant temperature fill the room with (heat) radiation moving in all directions with the speed of light, each molecule being in dynamic equilibrium with its neighbors because it emits as much radiation as it receives. The radiation theory assumes that the ether of space in general is somewhat similarly constituted except that the etherial radiation is of far shorter wave length than that due to temperature, and hence is super-penetrating to matter. The X-rays, gamma-rays and cosmic-rays are of wavelength intermediate between ordinary light and heat and this assumed etherial radiation. The theory further assumes that matter, as well as light, is a modification of this all pervading field of radiation which re-emits radiation in a form slightly less effective in causing pressure than the normal, and that all changes of motion thereof are caused by unbalanced radiation pressure, either in the etherial field or some modification of it. A tendency of all abnormal radiation to return gradually to the normal is also assumed. The adequacy of the theory to explain change of motion therefore rests on the fact that radiation produces a pressure on bodies which absorb and re-emit it; and it is of interest to Dartmouth men to recall that this fact was first demonstrated, and this pressure first accurately measured, in Wilder Hall by the joint labors of Professor Hull and former President Nichols both of Dartmouth College. The theory, indeed, is pretty much a Dartmouth product, for in its formulation I have depended much upon the generous assistance of Professors Proctor and Wilder, and of Dr. George Snell (Dartmouth '26). None of these, however, is responsible for any errors I may have made, but all of them for aid in avoiding error.
A considerable number of consequences are already inferable from the radiation theory and others are gradually appearing as the subject is studied. In a recent paper before the American Philosophical Association I listed 17 verifications covering a rather wide field of physical phenomena, and it is these, I apprehend, which aroused public interestfor after all, verification is the best test of truth. Despite encouraging confirmation by the facts, however, the theory remains only a speculation, for the evidence is by no means complete. A refutation may appear at any time, though none has appeared thus far.
If the radiation theory is correct in assuming that change of motion is due to radiation pressure, then bodies in relative motion should be subject to pressures deviating from those to which they are subject when not in relative motion, because of the Doppler-displacements inseparable from the motion of radiating bodies. The familiar Doppler-effect, described in textbooks of physics is the visible manifestation of such displacements. Now it is these radiation-displacements accompanying relative motion which link the radiation theory and the relativity theory together. For the former theory interprets the relativity effects, not as "relativities" of time and space, but as Doppler-displacement effects in the etherial (and other) radiation which causes change of motion. If this interpretation is correct, then relativity effects should have thefollowingcharacteristics, because Dopplerdisplacements do:
They should (1) be a maximum in directions coinciding with the motion of bodies, (2) be zero in transverse directions, (3) approach zero as the velocity of bodies approaches zero, (4) approach infinity as the velocity approaches that of radiation, (5) be direct functions of the index of refraction of the medium through which bodies are moving, (6) apply to the radiation-displacements involved in the Doppler, Fizeau and Airy"effects (upon light), and agree with the classical (non-relativity) formulae expressing them.
Relativity effects are found to have all these characteristics, and others inferable from the radiation interpretation which, for lack of space, cannot be here enumerated. Indeed the strength of the theory resides in the large assemblage of coincidences which must be considered merely casual if the assumptions of the theory are denied. Either then the theory is true, at least in its essentials, or an array of coincidences apparently unparalleled in the history of science, await explanation.
