Physicists are fond of telling us that space is really empty. Imagine that you could shrink by a factor of ten billion (in size, not calories), and walk around amongst the atoms. What would the world look like? Even in a dense material, such as platinum, it would look mostly like empty space. Here and there you would see some tiny wiggles: electrons flying around nuclei that are away off in the distance, much like the earth flying around the sun.
James Clerk Maxwell (1831-1879) and his contemporaries didn’t believe that a vacuum was empty space. They thought it was really filled with the ether, a mysterious substance somewhat analogous to the way in which our atmosphere is filled with air. Just as air is invisible, the ether that fills vacuum space is also elusive. So is there such a thing as empty space or a true “vacuum”? Yes—outside the universe in which we reside. Our universe is filled with the ether.
Why did Maxwell “invent” the ether? Sound is transmitted as molecules of air, say, push and pull each other, like tiny springs. Maxwell discovered that an electromagnetic field (EMF, such as light and radio waves), is propagated through a vacuum; he explained the transmission as being mediated by “molecules” of ether, which push and pull each other, again like tiny springs. In fact, the analogy between sound and EMF waves is much more extensive than hinted at here [an interesting table of comparisons is given in Return of the Ether, SciTech Publishing, 1999 (page 30)].
If material bodies such as electrons and nuclei occupy a minuscule proportion of space, and the remainder consists of the ether, we should pay more attention to research that will uncover the ether’s characteristics. However, physicists consider this to be backtracking because they abandoned the ether, around 1920, as an unnecessary embellishment, distraction, and complication. But there is plenty of reason to argue that the “big shots” of physics were too hasty. If the ether does exist, then the ether IS the universe in the sense that it far exceeds, in volume, that of the material matter floating around in it. And if the universe is expanding, this huge blob of ether is expanding, and destroying with it two of the sacred tenets of cosmology: In a vacuum, (1) the speed of light is everywhere constant at 300,000 kilometers/second (186,000 miles/second), and (2) the speed has never changed for billions of years.
We pretty much know everything about the way sound is transmitted. The velocity only depends on two characteristics: the density (weight) of the material, and the elasticity (ability to bounce back) of the material. A simple equation then yields the velocity of sound in that medium. For air, the velocity is around 330 meters/sec; for water 1530 meters/sec; and so forth.
The ether has what corresponds to density (it is called permeability) and elasticity (which is the reciprocal of permittivity). The same equation used for sound velocity yields the EMF velocity in any medium, including a vacuum.
All of this is a convincing argument for the presence of an ether. But the ether suffered a near-fatal blow in 1887 when measurements showed that the velocity of light was not affected by the earth’s motion through the putative stationary ether. There are two explanations—either the ether doesn’t exist, or every large object carries its own ether along as it hurtles through space, much as the earth carries its own atmosphere. Unfortunately, the latter explanation is a very unlikely scenario for most people, and they have trouble swallowing it. Just try to visualize the sun, earth, moon, and so forth, each as a blob of ether flying through space, like a comet. There also has to be a transition zone, surrounding each massive object, in which the ether’s velocity gradually trails off to the background “zero.”
But the situation is not as unbelievable as it first appears; it is a matter of relativity, as they say. We are dealing with motions that are slow compared to the speed of light: earth around the sun, moon around the earth, and so forth. For example, the earth flies at 30 kilometers/second around the sun, but this is only 0.01% as fast as the speed of light. Therefore, if the speed of light changes in a transition zone (because the ether of necessity has to be compressed or expanded in the transition zone), the effect is very small—hardly worth mentioning or measuring (even if we could). The same holds for the movement of the ether in intergalactic space—it is too slow to be of consequence relative to the velocity of EMFs. Research should be directed at detecting, or forever putting to rest, that putative 0.01% change in EMF speed as the ether is compressed on one side of the earth and expanded on the other side.
The ether may be closely linked to gravity, which is another mysterious characteristic that becomes appreciable between massive objects such as the sun, earth, moon, etc.
But what was the speed of light 10 billion years ago? Many cosmologists have wondered if this and other natural “constants” have changed with time. Without the ether, there was no basis for this possibility—only wild conjecture. If there is an ether, however, substantial change is practically guaranteed. Ten billion years ago the universe was much smaller, so the ether was compressed. In the case of a sound wave, the velocity depends on density and elasticity, which of course change as the material is compressed. Analogously, for an EMF, does the velocity increase or decrease as the ether is compressed? It could go either way; as stated above, EMF velocity depends on permeability and permittivity; but we cannot simply take a container full of ether and compress it to make measurements (remember that the walls of any material container are almost completely nonexistent insofar as the ether is concerned). However, we routinely measure the permeability and permittivity of material that is immersed in normal, “uncompressed” ether in the laboratory.
The ether makes the expansion of the universe much more palatable. It places a definite boundary on the universe. Beyond the outer surface of the expanding blob, there is nothing—no electrons, atoms, stars, galaxies, or universe. This is what we expect. In an infinite universe, Heinrich W.M. Olbers pointed out around 1800, wherever we look at night, the integrated effect of distant, and yet more distant, stars and galaxies should yield nothing less than a bright “sunlit” sky everywhere. Because the night sky is uniformly dark, this is one of the strongest arguments that the universe is finite.
Cosmologists could go into shock if there is evidence that any of the natural constants have changed. It could topple many of our cherished institutions, such as the expansion of the universe and the Big Bang. In the meantime, until we can explain why the constants have their particular values, there is no assurance that they are really “constant.” So did cosmologists invent string and other bizarre theories to elucidate what the ether theory can better explain? Perhaps.