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3

Typical accelerating masses will generate gravitational waves. but because gravity is so weak of a force; and current/plausible near future detection apparatus will be unable to detect signals from anything less dense than gravitationally stable masses of degenerate matter (ie neutron stars or white dwarfs) moving at near relativistic speeds.


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Leckner's paper deals with the effect of induced polarization on the spheres. Electrons are redistributed, making the force different from what one would expect. The gravitational counterpart is tidal distortion: since the gravitational field is non-radial when you have two heavy masses close to each other, matter will move to make the surface an ...


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You don't need to model it if you assume the universe is homogeneous and isotropic. If it is, then any uniform shell of material has absolutely no gravitational effect on anything inside the shell. This is true in Newtonian physics and in GR. https://physics.stackexchange.com/a/43640/43351 It is still not known whether the universe is infinite, but it is ...


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We don't know… We don't know how much Universe there is outside our observable Universe. The observable Universe seems to have a "flat" geometry (in the 3D sense, not in 2D). If it really is globally flat, then it just goes on and on forever, i.e. there is infinite mass. However, just as Earth looks flat on small scales, it might very well be that the ...


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Theoretically you can create a black hole from just energy. Although the amount of energy required to be focused in one spot is impractically huge. And why it’s easier to do it with matter. So the energy inside the sun should still contribute to its gravitational effect on other bodies until it exits the surface.


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