Medium entrainment considered as flow

It is not my idea. It is the way energy and force work.

You cannot apply a force to something if you are not touching it. If it is too far away for you to touch it directly, you can touch it indirectly by throwing something at it. If you hit it, that impact applies the force which you could not apply.

Note that if you miss it, no force is applied. But you still spent some energy. Which you created by applying force to the thing you threw, while you were touching it. Perhaps the thing you threw will eventually hit something else, and apply a force to that thing.

In order for gravitational force to exist, there has to be gravitational energy. A lot of particles or a lot of waves[1] moving around the universe all the time, pushing things toward one another when they hit something and apply a tiny push (a force) to to it.

Each mass has a gravitational force (energy) field around it. Much like each magnet has a magnetic force (energy) field around it.

LB

[1]
Could it be something other than particles or waves? Physically, these are all we know of so far, but 'other' is still possible. Until we can actually detect the energy mechanism (the force carriers) in one or more of these force fields, it would be foolish to rule out some as yet undiscovered doohickey.
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Dark matter and dark energy are 'wild ideas' that are being floated in an effort to explain some experimental and observational anomalies. Something too small to detect directly, is one common way it is described.

The two particle fields we have postualted to explain EM energy (force) and gravitational energy (force) look like they might also explain some other of these anomalies.
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Time might actually have physical existence. And it might therefore actually be possible for physical things like gravitational potential or speed to change time physically. And so on.

We can't detect space-time. We do not have a single device that can take a single measurement in 4D space-time. All of our toys work in 3D space plus 1D time.

Einstein's equations are said to have been tested by experiment. But this is not exactly true. His equations are all 4D, and we can't test in 4D. So we have to convert his equations from 4D to 3D plus 1D. Then we can test the 3D plus 1D equations. They are approximations in many cases (no exact translation available). But we can add as many terms to the series expansion as we need to match or exceed the precision or our experimental apparatus. It works fairly well.

<b>[Jim] "... it matters not what you call these things. "</b>

Well, no, and yes. We cannot talk (or even think) about a thing until we have a label, a name, for it. And it truely does not matter what noise we make when we want to refer to some specific thing. But it does matter that we all use the same noise. And it matters that we all attach the same meaning to that noise.

It is a fact of life that we still have problems in this regard. Communication problems are everywhere. And the worst part of it is, often we do not realize it.

We do OK, all in all. But there is room for a lot of improvement.

Earth never touches Luna, but it continuously accelerates Luna. (And Luna continuously accelerates Earth.)

a = f/m

A force is needed to make the acceleration happen. Earth must be applying a force to Luna. But Earth never touches Luna. (Directly, at least.)

How does this happen?

Gravity force causes acceleration. Energy is everywhere doing nothing or maybe doing something if forced to do it. Energy will flow when forced to do so or will lay around if not being forced. Gravity is the force that makes things happen. There needs to be a clear distinction made between these basic properties. As for your question how-I don't know and if I did I would not be looking for it. You have not addressed my question about gravity energy, have you?

Yes. Several times.

Perhaps you need to rephrase it?

"Where it concerns the Sun, the gravitational potential is not dependent on the propagation speed."

The propagation speed is the same for all masses (Sun and planets), but since the Sun is (almost) static relative to the reference frame of the Solar System the shape of the gravitational field is not dependent on how long it took to build up.

Since the planets are not 'static' relative to the reference frame of the Solar System, their gravitational fields are changing all the time. The pace at which the gravitational field moves forward (along with the planet) depends on the propagation speed.

As a consequence, the Earth is attracted towards the 'retarded position' of the surrounding planets which is dependent on the propagation speed of gravity. The Earth is attracted towards the 'actual position' of the Sun because the gravitational field is completely symmetrical.


"Drag is a type of friction."
Friction transforms kinetic energy into heat (as long as the friction is not static).
Drag is a force applied on a mass in a direction opposite to the movement (whereby friction is one way to create this force, but it is not the only mechanism).

In a friction-free environment, the decrease in kinetic energy available with the mass (as a consequence of drag) must result into an increased kinetic energy applied to the medium. An increasing amount of medium will become dragged up to the moment when all medium is having the same velocity as the mass. (all medium = all medium on the circular path around the Sun)