The existence of a luminiferous aether has never been disproved – it was just thought to be unobservable and hence not very useful. However, if the luminferous aether is also a universal background field responsible for inertia effects it gives rise to predictions that can be tested by experiments. If validated the combined theory would be relevant to some of the serious issues now facing modern physics. One such experiment is suggested in this essay.
Introduction
The idea that light travels in a medium persisted for over 400 years and was thought to be true by scientific greats including (in temporal order) Robert Boyle, Isaac Newton, Christiaan Huygens, Thomas Young, Augustin-Jean Fresnel, Augustin-Louis Cauchy, George Stokes, James Clerk Maxwell, Hippolyte Fizeau, Heinrich Hertz, Hendrik Lorentz, Henri Poincaré and Albert Michelson. Aethers in general have a colorful history. Quoting from the Wikipedia article titled Luminiferous aether:
“By this point [~1878] the mechanical qualities of the aether had become more and more magical: it had to be a fluid in order to fill space, but one that was millions of times more rigid than steel in order to support the high frequencies of light waves. It also had to be massless and without viscosity, otherwise it would visibly affect the orbits of planets. Additionally it appeared it had to be completely transparent, non-dispersive, incompressible, and continuous at a very small scale. James Clerk Maxwell wrote in Encyclopædia Britannica [1878]: “Aethers were invented for the planets to swim in, to constitute electric atmospheres and magnetic effluvia, to convey sensations from one part of our bodies to another, and so on, until all space had been filled three or four times over with aethers. … The only aether which has survived is that which was invented by Huygens to explain the propagation of light.”
Towards the end of the 19th century experiments trying to discover how the speed of the Earth affected the measurable two-way speed of light could find no effects at all. This was taken by many as evidence that the concept of the aether was non-viable. However, Lorentz and Poincaré eventually came to realise that the experiments had actually discovered relativistic length contraction and time dilation. Einstein achieved the same results simply by postulating that the speed of light is constant in all inertial reference frames. This led to relativistic length contraction and time dilation through pure logic. Since it seemed the luminiferous aether was undetectable and Einstein’s new approach was a lot more profitable, interest in the aether idea faded almost completely away.
Contrary to some texts, the failure to find evidence of an aether drift did not prove that the aether was non-existent. Indeed, with what we now know about Lorentz length contraction and time dilation we would not expect such experiments to detect an aether drift arising from the passage of the Earth through the aether.
Nor did the Einstein’s theory of Special Relativity prove the aether does not exist. In a sense, the final Lorentz-Poincaré concept of the aether predicts length contraction and time dilation while the theory of Special Relativity effectively assumes them.
It is also generally assumed that luminferous aether was shown to be undetectable. Contrary to that view, this essay will suggest some simple experiments might be possible that unambiguously do reveal the luminferous aether.
Einstein was instrumental in pushing the idea of a luminiferous aether aside but even he believed it existed. In 1920 he wrote: “We may say that according to the general theory of relativity space is endowed with physical qualities; in this sense, therefore, there exists an aether. According to the general theory of relativity space without aether is unthinkable; for in such space there not only would be no propagation of light, but also no possibility of existence for standards of space and time (measuring-rods and clocks), nor therefore any space-time intervals in the physical sense. But this aether may not be thought of as endowed with the quality characteristic of ponderable media, as consisting of parts which may be tracked through time. The idea of motion may not be applied to it.”
Note that in 1920 Einstein did not realise that the Milky Way is just one galaxy amongst countless others. Nor did he have the benefit of knowing that in 1967 a major discrepancy would be discovered between the expected speeds of stars in spiral galaxies and the rates observed through telescopes.
Q Theory and the Luminiferous Aether
Previous essays in this series (van de Vusse, 2024) have suggested a background energy field dubbed “Q” as being responsible for inertial phenomena, Mach’s Principle and the apparently anomalous rotation speeds of stars in spiral galaxies.
It would seem extravagant to have two physical fields filling the whole Universe. Accordingly the Q field hypothesis is extended to suggest that the Q field is in fact one and the same as the elusive luminiferous aether.
This immediately brings into play thousands of experiments on light and hundreds of theories about light and gravity and everything in between.
If the Q field hypothesis can survive being tested against all such relevant experiments it would create very interesting new insights, understandings and lines of enquiry.
Test for Q effect on the travel time of light
Attempts to detect an aether drift effect on the two-way speed of light using closed path laboratory experiments and the Earth’s orbital speed around the Sun fail because of relativistic length contraction and time dilation. A different sort of experiment is required. The proposal below looks for delays in the time taken for distant light to travel through one side of an intervening galaxy as compared to the other.
Observing gravitational lensing around stars, galaxies and clusters of galaxies is now an established part of astronomy.
What we need for this experiment is a spiral galaxy which is more or less edge on to our line of sight and which is already producing a double image or multiple images of some very distant sources of bright light, such another galaxy.
We then need a distant event to occur in the source light. A supernova will do nicely, but a fluctuating quasar might also suffice. In fact, any sudden change in the light from the far source will do. As soon as something is detected in one of the images then set up a watch and wait on the other image.
It is to be expected that light travelling from a bright distant source and taking two distinct paths to reach our telescopes will take longer to travel along one path than the other. The Shapiro effect involves a small time delay when light passes across a gravitational well and this has been measured for light passing to close the Sun. In fact this is now regarded as one of the tests for Einstein’s General Theory of Relativity.
However, what we are looking for is a gross time difference of the order of anything up to a few years.
The hypothesis goes as follows. (1) The difference between the observed speeds of orbiting stars in the discs of spiral galaxies and the expected Keplerian speeds is due to dragging of the inertial reference frame within and around such galaxies. (2) The inertial reference frame is akin to a physical vacuum energy density field (code named Q). For more details on this hypothesis, plus a list of associated experiments and predictions, see Essay 1.1 in this series (van de Vusse, 2024). (3) The Q field is also the medium in which light travels. If there is any movement in the Q then light will make better progress through the Universe if it travels with the flow of the Q rather than against it. (4) If light from a distant source is lensed around both sides of a galactic core, then it will arrive notably sooner if it travels in the pro-grade direction than if it travels in the retro-grade direction.
A specific estimation of the predicted extra time delay can be made once the size of the intervening galaxy and the difference between the Keplerian and observed orbiting speeds has been estimated. An approximate estimate is simply Dv/c2 where D is the distance the light travels through the galactic disc and v is the average boost or headwind experienced from the clockwise drag of the Q (aether).
A variation of this experiment might be possible within the Milky Way if light from a local supernova is reflected from dust or other matter in various parts of the disc and thence into our telescopes.
Q and the Passage of Light
One of the amazing things about ‘light’ (electromagnetic radiation generally) is that high energy gamma rays can deliver energy at frequencies 21 orders of magnitude greater than low energy radio ‘waves’. If we used the concept of wavelength (which we avoid for reasons explained in Essays 3.1-3.8 of (van de Vusse, 2024)) then the wavelength varies from 10-15 metres to about 106 metres. Does any other fundamental physical entity in the Universe come in such a range of sizes?
If we used the concept of a photon being some sort of particle then this phenomenal range would pose problems. For example, how could a photon entity a billion billion times ‘bigger’ than another photon travel at exactly the same speed through some interstellar medium.
Conjecture: When a phot travels through the medium of interstellar space, the only thing that travels is energy. And the reason that this energy travels so fast tells us something about the nature of that medium. In essence it has to be rigid enough so that the input of energy is one place can be felt at another place 3×108 metres away one second later.
This conjecture might be right or wrong but it does illustrate the overall process/protocol. Accumulate evidence before making assumptions about what is going on and keep an open mind as to what the answers might be.
Summary
Michelson and Morley tried to find evidence of an aether drift but instead discovered Lorentzian length contraction and time dilation, though they did not realise it. While Fitzgerald, Poincaré and Lorentz were unravelling all the implications Einstein reached the essential conclusions simply by postulating that the speed of light in inertial reference frames is a Universal constant. Contrary to common belief the idea of a luminiferous aether was never disproved – it was just bypassed.
A century later and physics finds itself in a deep hole. It cannot explain the gross movements of stars in spiral galaxies and the conjectured explanation involving huge amounts of exotic cold dark matter is running into the awkward problem that none of it can be found and the list of potential candidates is all but exhausted.
The first essay in this series offered a new potential explanation for this “galactic rotation curve catastrophe” by introducing a Universal background energy field responsible for giving rise to mass and inertia generally. Far from being abstract or unobservable a range of experiments was suggested to test the idea.
Simply for the reason that it having both a background energy field (dubbed Q) and also a universal luminiferous aether would be extravagant, this essay has conjectured that they are exactly the same field. This immediately gives rise to testable predictions. The experiment suggested here is to look for delays of a year or more in the time light takes to travel through a spiral galaxy rim in the pro-grade direction as compared to the retro-grade direction.
A successful confluence of the Q field idea and the old luminiferous aether idea would open the way to new insights and discoveries. Or not – it could be totally wrong. The good thing is that it open is to experimental testing, and quite easily at that. Given the serious problems in modern physics it might be worth serious consideration.
Reference
Van de Vusse, Sjoerd B.A., 2024, Some ideas and experiments for issues affecting modern physics, https://hereticalphysics.com.au
Author contact: SBAvan@utas.edu.au
Author’s location: Hobart, Australia
