A NEGLECTED TYPE OF RELATIVITY.
THE negative result of all experiments to detect the earth's motion through space by its effect on terrestrial phenomena positively requires explanation, and the modern principle of relativity is generally conceded to be the most successful attempt to explain so far made. The principle has, however, led to great complexity in detail and its implications have not yet been completely worked out.
It does not seem to have been generally noticed in this connection that if the velocity of light is assumed to depend on the velocity of the source, in the same way in which the velocity of a bullet depends upon the velocity of the gun, then we have a simple type of relativity which in many ways presents a striking contrast to the principle now in vogue.
Such a light-velocity is not obviously consistent with the conception of light as a wave motion in a semi-material medium, but if there is anything that modern discoveries in fundamental physics have shown, it is that we must not reason too much from analogy or expect to find the most fundamental of all transformations of energy to resemble those transformations which we are familiar with in complex material systems.
The assumption that the velocity of light depends on that of the source has, so far as the author is aware, never been properly examined. This is strange, but is probably explainable as a natural result of the complete trust which has been put for years in the conception of an ether.
In the paper of which this is an abstract, the astronomical consequences of the assumption that the velocity of light depends on the source-velocity, in the same way that the velocity of a bullet depends on that of the gun, has been partially developed. It is found that a change in the line-of-sight-component of a star's velocity causes the time interval between any two events which happen on the star to be different from the apparent time interval between the same events as observed from the earth. If the star is very distant and changes its velocity as in the case of a binary star, it is even possible that two events may appear to happen in their reverse order.
In the case of spectroscopic binaries certain characteristic peculiarities should appear in the spectrum, peculiarities which apparently do not exist. The investigation is only just begun but so far the indications are rather against the existence of the effect.
- 1Abstract of a paper presented at the Princeton meeting of the Physical Society, October 23, 1909.