Answer:
Special Relativity/Newtonian Physics
Step-by-step explanation:
Well in Newtonian physics you could say your mass is pushing you down and the floor is pushing you up. But rather in Special relativity only to floor is pushing up on you.
In this theory the word inertial observer matters and proves several matters throughout science. So exploring is a huge important thing to do. A person cleaning the window falls, while doing so the person feel weightless while falling. Objects that fall down with the person would remain stationarily, relative to the person. Similar to a person in space. Far away from any large masses the person would be an inertial observer. With no acceleration the person is also not close to gravitational fields and all laws of physics in the person's reference frame. The man falling off the roof is an inertial observer too. Because of this both of the matters about the rocket man and the person falling off the roof are the same.But you would think that the person falling off the roof is accelerating. But the equivalence principle tells us wrong.
The equivalence principle has made it easy to prove both people in the situations are inertial observers. People watching would think that he is accelerating, but he is not. But he is accelerating? The equivalence principle tells us to focus on the experience of the observer and the person feels weightless so they are an inertial observer. If a person in Space comes across a planet, the person's rocket will start heading towards a planet. But the Space person would be oblivious. The person would not feel any acceleration. The spaceship would not sense any acceleration nor would it sense that it is turning. A person outside the spaceship may see the slight curving motion and the person inside would not notice until the instant it crashes into the planet. Explaining this is geodesics and spacetime it equally links and connects with this in an obvious and common way.
Spacetime is a model that makes 4D, it joins space and time, ‘Space-time’. Now people can say how it perfectly describes gravity with it’s queer way of curving.
But how does this happen without gravity? Space is 4D with width, breadth, height and time. There is a model called spacetime. Einstein along with many other people visualise it as woven along with time. Space- time. It curves by mass distribution. The person is still traveling in a straight line. Just straight through spacetime. It is traveling along the geodesics of spacetime. This is actually quite common, it is just an object travelling straight on a curved surface. Like an airplane travels straight to get quicker to a different place. But it appears curved because obviously the Earth is curved. So if you unfolded the earth the path would be curved, but the plane is still traveling in a straight line. Let’s also say you and your friend were standing on the equator. You are 1000 kilometers apart from your friend. As you move towards the north direction you would eventually meet with your friend. You are not being pushed by gravity but simple as that you are just traveling on the geodesics of Earth. Matter tells spacetime how to curve, Spacetime tells matter how to move-John Wheeler.
The man falling off the roof was accelerating so what happens if the rocket man accelerates?
Now once the rocket man accelerates the floor accelerates into rocket man. Objects remain stationary but the floor also accelerates into the objects. The situation is just like on earth except you are not an inertial observer because you do not feel weightless. The observer inside the rocket would feel a force pushing up on the feet. Same on earth. You are accelerating in order to remain stationary. However you can not see yourself accelerating. In Newton’s rule the force of Gravity would be pushing you down and the ground pushing you up. However in special relativity gravity does not exist so it’s just the force of the ground pushing up on you. Just like the rocket accelerating. You look like you are not accelerating up but only in your frame of reference. To measure your speed of acceleration you must get an inertial observer to measure your acceleration speed. Like the man falling off the roof. Let’s say you are in the building and the man falls off the roof. To him you would appear accelerating upwards. So you have to accelerate just to stand still. Why all objects fall at the same rate is a mystery to Newtonian Physics but it is not a mystery to Special relativity because the objects are not accelerating just the floor accelerating into it.
So I hope you understand now, I think you know what I'm getting at. Might of misunderstood your question.