Absolute motion is defined as follows:
Absolute motion is not relative as it has a single very well defined speed.
Absolute motion is furthermore independent of the motion of its source and independent of the motion of the observer.

It turns out that both the motion of light in vacuum and the motion of sound in air at 15 degrees C are absolute.
Everyone knows about light’s absolute speed of 300,000Km/s.
The speed of sound is 340 meters per second; and proof of sound’s absolute speed is that supersonic planes are able to catch up the sound they emit, showing the propagation of sound is independent of both its source (the plane) and its receiver (also the plane).

As such, it makes utterly sense, as I shown next, to treat light and space by analogy to sound and heat.
This chapter is at the image of chapter 2.
The model of space looks like the model of temperature, while light and sounds models look alike.
Space, in gravimotion, occurs (rather than is) as Maxwellian motion or confined-activity type motion (introduced in sections ).
Space's Maxwellian motion has much more thrust than confined-activity though.
And because space's Maxwellian motion involves no matter it is given the name pure-activity.
As such pure activity, which is none else than the , is as mentioned in section constituted of motion quanta.
Figure 3.1 is just as figure 2.2.2, but occurs as MQs instead of MOs.
And light waves ride pure-activity just as sound waves ride confined activity.

FYI light waves do not ride on a background in physics. Michelson and Morley in the 1890s made an experiment proving beyond any doubts there is no "aether" in space.
Unfortunately, quantum newer physics comes and nullifies the above older physics firm stand! The quantum vacuum is not empty at all but instead full of frantic energy!
This is another of those dualities physicists forgive themselves with so easily! And frankly I gave up trying to make sense of physics mathematical interpretation of Nature.
When I bring this subject up, I am often told that I do not understand science. And because this comment about my incomprehension of science is absolutely right, I discovered a very simple truth; I do not understand what is not understandable! According to science I am supposed to accept that space is totally empty and altogether full of frantic energy; in the spirit of science such absurdity is simply turned into a scanty discrepancy; the ultimate goal of science, am I now told, is to unveil laws that allow making predictions!
While predicting is admirable, physicists themselves also unfortunately use science to explain things to us laypersons. And when physicists make explanations based on their mathematics, rather than mind their own predictions, I am personally compelled to meddle and bring in gravimotion.
Here is the bargain: I recognize that unveiling laws and predicting as done in science is of the essence; in return I am asking physicists to recognize that claiming that space doesn't exist and exists altogether is pure nonsense!

Both space and time are dislodged and replaced by motion of pure-activity type, a cousin of the quantum vacuum. Instead of being empty, space is an entity of its own and a live entity at that, constituted of motion-quanta, the fastest motion in Nature.
Space occurs as motion-quanta that are invisible to human eyes unless activated or turned-on by light (next section), and we will see also activated through gravity (next chapter).

The hierarchy established by our human minds, and kept as is in the science of physics, which is that motion occurs in space, is in gravimotion tipped-over, down side (motion) up (above both space and time).

Space and time have no longer any raison d’être in gravimotion.
Pure-activity dislodges them both, and defines the present mo(ve)ment at the bottom of the

7. Earth’s daily spin on itself.
6. Earth’s yearly revolution around the sun.
5. The motion of our Solar system within our Milky-Way galaxy.
4. The spinning of our galaxy.
3. The overall motion of our galaxy.
2. ... there is here a missing link ... filled-in next chapter.
1. Finally the very constitution of the present or the present mo(ve)ment that is pure-activity, which is occurring as motion-quanta.

One last comment is that pure-activity (space) amounts to motion-density. Should there be variations in motion-density within pure-activity, one imagines that these variations would even out in accordance with the We will see that motion-density is the essence of electrical fields. In gravimotion it is because the motion-density of pure-activity is even, that pure-activity (space and time) is neutral electrically.