The Ether of Space

by Sir Oliver Lodge

In order to set up a tension equal to what is here suspected of being a critical, or presumably disruptive, stress in the ether [10³³ c.g.s.], a globe of the density of the earth would have to have a radius of eight light years. In order to generate a velocity of free fall under gravity equal to the velocity of light, a globe of the earth's density would have to be equal in radius to the distance of the earth from the sun, or say 26,000 times the earth's radius. If the density were less, the superficial area would have to be increased in proportion, so as to keep ρ R² constant.

The whole visible universe within a parallax of ¹/₁₀₀₀ second of arc, estimated by Lord Kelvin as the equivalent of 10⁹ suns, would be quite incompetent to raise etherial tension to the critical point 10³³ c.g.s. unless it were concentrated to an absurd degree; but it could generate the velocity of light with a density comparable to that of water, if mass were constant.

If the average density of the above visible universe (which may be taken as 1.6 × 10^-23 grammes per c.c.) continued without limit, a disruptive tension of the ether would be reached when the radius was comparable to 10¹³ light years; and the velocity of light would be generated by it when the radius was 10⁷ light years. But heterogeneity would enable these values to be reached more easily.

Gravitation is thus supposed to be the result of a mechanical tension inherently, and perhaps instantaneously, set up throughout space whenever the etherial structure called an electric charge comes into existence; the tension being directly proportional to the square of the charge and inversely as its linear dimensions. Cohesion is quite different, and is due to a residual electrical attraction between groups of neutral molecules across molecular distances: a variant or modification of chemical affinity.

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APPENDIX 2

CALCULATIONS IN CONNEXION WITH
ETHER DENSITY

Just as the rigidity of the ether is of a purely electric character, and is not felt mechanically—since mechanically it is perfectly fluid,—so its density is likewise of an electromagnetic character, and again is not felt mechanically, because it cannot be moved by mechanical means. It is by far the most stationary body in existence; though it is endowed with high intrinsic energy of local movement, analogous to turbulence, conferring on it gyrostatic properties.

Optically, its rigidity and density are both felt, since optical disturbances are essentially electromotive. Matter loads the ether optically, in accordance with the recognised fraction μ²−1 / μ²; and this loading, being part and parcel of the matter, of course travels with it. It is the only part amenable to mechanical force.