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Mass universe is constituted of micro / macro mass natural bodies/systems. It is known that the mass (micro / macro) natural bodies is concentrated mainly in neutrons, protons and electrons as entities with a certain stability, fig. 3. Fig. 3. (Electro)convergence of the electron/neutron /proton, )[4] 1- Neutron matrix (local substantial body/ local wave ...


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yes you will be pushed up to the ceiling of elevator because you are accelerated inside the elevator due to gravity and the elevator itself is accelerated due to external faster acceleration, that makes you stuck on the elevator ceiling then they ceiling will push on you with normal force making you move with the elevator downward


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I think one can enter a dispute regarding the notion of "accepted" but the idea is that General Relativity is successfully described by a Pseudo-Riemannian Manifold, subject to Einstein Equations, with free-falling objects following geodesics. Now you look for a set of axioms that give you this structure. One such set, although not entirely rigorous, is ...


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General relativity can be constructed from the following principles: The Principle of Equivalence Vanishing torsion assumption ($\nabla_XY-\nabla_YX=[X,Y]$) The Poisson equation (or any other equivalent Newtonian mechanics equation) Explanations: The Equivalence Principle can be used to show that spacetime is locally Minkowskian, i.e. the laws of ...


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But then someone talked to me about Principle of Equivalence and not possibly being able to identify what is proper acceleration and what is coordinate acceleration with an accelerometer. Is it true ? That's not true. By definition, an ideal accelerometer measures proper acceleration. It appears you (and possibly the acquaintance who talked to you) are ...


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No. Yes, because the forces only depend on the separations. (Translation symmetry.) Elaboration of 1.: We have $\mathbf{x}'=\mathbf{x}-\tfrac{1}{2}\mathbf{g}t^2$. Let us calculate the acceleration: $$\frac{d^2\mathbf{x}'}{dt^2}=\frac{d^2}{dt^2}(\mathbf{x}-\tfrac{1}{2}\mathbf{g}t^2)=\frac{d^2\mathbf{x}}{dt^2}-\mathbf{g}$$ Thus the force is ...


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The event horizon is a null surface, which means that if you pick a very small region of spacetime that straddles the event horizon, small enough that the equivalence principle should apply, then any local inertial frame in this region should measure the event horizon to be moving outwards at the speed of light. Slower-than-light objects in this region can ...


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Let's call the formation "spear". And we call an observer inside the free falling lab "Labguy". And an observer at infinity we call "Farguy". The spear is thrown out of the lab. Labguy says: "The spear keeps moving at constant speed, and its length stays constant" Farguy says: "The spear's velocity compared to the local speed of light near the spear is ...


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Escape velocity is unnecessary, and a red herring anyway. You seem to be equating general relativity with black holes, but the latter are just a small part of the former. Moreover, the fact that the "escape velocity" from a mass $M$ equals $c$ at the Schwarzschild radius $2GM/c^2$ is an unfortunate coincidence. An event horizon has nothing to do with escape ...


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I think he meant that there are no other forces acting on them except gravitational therefore nothing to slow them down/accelerate them more than the other.


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In general relativity, the gravitationally free-falling objects are inertial, while you standing on the Earth's surface are accelerated upwards by the force provided by the floor you're standing on. That is why you see the objects as accelerating downwards--because you are in an accelerated frame. Therefore, your understanding of mechanics on this probably ...



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