To sum that up an object seeks equilibrium based on it's density. It goes up if its less dense than the air surrounding it and down if its more dense and can't pass through a solid ground. Atmosphere is stacked so that it's more dense on the bottom. Roger that and this is the only assumption I'am using to argue against denpressure along with principle of inertia and conservation of energy. I believe that in your explanation you accepted these as well.
No. An object doesn't. Atmosphere does. The object interferes with equilibrium when in motion by energy applied to it.
In lift/aircraft example the key was isolation from it's surrounding air pressure. Air pressure outside the lift/aircraft is not equal to inside. There is an isolated mini atmosphere inside the aircraft. Door is closed and no windows. Can you measure or observe atmospheric conditions outside? Like train on constant motion. You cannot feel it unless the train is turning or accelerating/decelerating.
Ok, hopefully you may get this.
Let's use a train as an example.
Inside that carriage at rest, you are equal in pressure to the outside. Fair enough?
Ok, once that carriage starts to move, you are now changing that pressure acting upon you. You are changing it into compressed air without freedom of escape, unlike the air outside that is compressing but can escape over the actual carriage itself.
Try and think hard on this because it's key to undertstanding.
You see, once you are in motion in that carriage, your body is under more pressure. It's minor but it's there. It becomes stronger depending on acceleration. As soon as the carriage becomes a constant speed, your body equalises insaide that carriage. You still don't notice any real pressure because of this equalisation.
Just for the sake of it, think of that carriage accelerating from that point, let's say you're doing 50 mph and in 5 seconds you have accelerated to 200 mph. You will feel this compression upon you because the air inssiode the carriage gets compressed to the back as the air outside seeps in to add to that pressure.
The result is, you get pushed back into your seat until that acceleration stops. Once that acceleration stops or becomes constant, you feel this as the compressed air what is being pushed to the back, evens up and equalises around you once again. You will feel this as a gentle push forward whilst equalisation takes place.
When free fall starts, experiencing from the inside suddenly you start to float. You don't fall towards the floor. How can this be explained via denpressure?
Denpressure is still evident from an outsiders point of view but is not evident from your point of view because the plane negated it by matching your fall rate.
What I can tell from your explanation this is possible in only if atmospheric pressure is zero or if density layers of cabin have disappeared and there is now a constant pressure.
The cabin is pressurised. Once that plane dives, it causes uneven air pressure. Basically the roof of the plane is pushing or compressing the air downwards but the plane is diving faster than it can push on you, so you basically push back on that, overcoming it easily with the aid of the planes power.
Lets think about latter for a moment. When you hit the ground the atmospheric layering must re-appear or else there would be no weight. Then someone comes and turns the container you were in upside down. What happens inside?
Ok, let's assume you're trapped in a glass ball under 15psi.
Your body takes up a certain amount of that ball pressure simply by your mass repelling it away from you.
The second you move, the atmosphere fills the area you were in whilst your mass/density has to displace the atmosphere you now put yourself in.
It's like putting a brick in a bucket of water. The water above is holding that brick on the bottom because that brick has displaced it's own mass/density against that water. A displacement and that displacement has to go somewhere, which it does. It goes right back above and around the brick, clamping it to the bottom.
That's all that's happening with us.
Obviously objects are not against sealing but what then appears to re-instate the stacking of air? What force is doing that and why are these stacks always orthogonal to earth? Don't air have inertia at all when you turn the container around?
All things push UP. The atmosphere is due to energy pushing things UP.
The more that energy pushes stuff UP, the more stacking there is and the more energy needed to push against.
Think of the Earth being flat as a pancake. Imagine the Earth has a big rubber membrane covering it. Let's call this , ice.
Ok now inside the Earth, energy pushes up solids and gases and liquids. It pushes up against the membrane which is now gaining in size. It's creating a dome.
The pressure needed to push up against it is minimal at first but as the gases build, they become more in mass and it takes a little more energy to push into it...and so on, until it becomes dense down below and less dense at or near the top.