"Doth not this aethereal medium in passing out of water, glass, crystal, and other compact and dense bodies in empty spaces, grow denser and denser by degrees, and by that means refract the rays of light not in a point, but by bending them gradually in curve lines? ...Is not this medium much rarer within the dense bodies of the Sun, stars, planets and comets, than in the empty celestial space between them? And in passing from them to great distances, doth it not grow denser and denser perpetually, and thereby cause the gravity of those great bodies towards one another, and of their parts towards the bodies; every body endeavouring to go from the denser parts of the medium towards the rarer?" - Newton
Write down your ether theory equation of motion.
Newton is referring to the state of displacement of the aether.
The aether does not grow denser and denser. The aether is, or behaves similar to, a supersolid. However, Newton is correct, displaced aether pushing back and exerting inward pressure toward matter is gravity.
""In several parts of this treatise an attempt has been made to explain electromagnetic phenomena by means of mechanical action transmitted from one body to another by means of a medium occupying the space between them. The undulatory theory of light also assumes the existence of a medium. We have now to shew that the properties of the electromagnetic medium are identical with those of the luminiferous medium." - Maxwell
Maxwell's displacement current is a physical displacement of the aether.
'Ether and the Theory of Relativity by Albert Einstein'
http://www-groups.dcs.st-and.ac.uk/~history/Extras/Einstein_ether.html
"space without ether is unthinkable"
"the state of the [ether] is at every place determined by connections with the matter and the state of the ether in neighbouring places"
The state of the aether at every place determined by connections with the matter and the state of the aether in neighboring places is the state of displacement of the aether.
'Interpretation of quantum mechanics by the double solution theory - Louis de BROGLIE'
http://aflb.ensmp.fr/AFLB-classiques/aflb124p001.pdf
“When in 1923-1924 I had my first ideas about Wave Mechanics I was looking for a truly concrete physical image, valid for all particles, of the wave and particle coexistence discovered by Albert Einstein in his "Theory of light quanta". I had no doubt whatsoever about the physical reality of waves and particles.”
“any particle, even isolated, has to be imagined as in continuous “energetic contact” with a hidden medium”
The hidden medium of de Broglie wave mechanics is the aether. The “energetic contact” is the state of displacement of the aether.
A moving particle has an associated aether displacement wave. In a double slit experiment the particle travels through a single slit and the associated aether wave through both.
"It is ironic that Einstein's most creative work, the general theory of relativity, should boil down to conceptualizing space as a medium when his original premise [in special relativity] was that no such medium existed [..] The word 'ether' has extremely negative connotations in theoretical physics because of its past association with opposition to relativity. This is unfortunate because, stripped of these connotations, it rather nicely captures the way most physicists actually think about the vacuum. . . . Relativity actually says nothing about the existence or nonexistence of matter pervading the universe, only that any such matter must have relativistic symmetry. [..] It turns out that such matter exists. About the time relativity was becoming accepted, studies of radioactivity began showing that the empty vacuum of space had spectroscopic structure similar to that of ordinary quantum solids and fluids. Subsequent studies with large particle accelerators have now led us to understand that space is more like a piece of window glass than ideal Newtonian emptiness. It is filled with 'stuff' that is normally transparent but can be made visible by hitting it sufficiently hard to knock out a part. The modern concept of the vacuum of space, confirmed every day by experiment, is a relativistic ether. But we do not call it this because it is taboo." - Robert B. Laughlin, Nobel Laureate in Physics, endowed chair in physics, Stanford University
Displaced aether pushing back and exerting inward pressure toward matter is gravity.