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Mekon
Dec3-10, 03:15 AM
Hello all,
If there are two planets of identical size but very different mass, why does one have a higher gravity than the other given that space/time is curved by each in the same way? Or does space/time curvature depend not on the size of a body but its mass?
TIA
Mekon

George Jones
Dec3-10, 04:07 AM
Spacetime curvature caused by a massive body depends on the body's size, mass, and spin. Curvature depends on the distribution and movement of mass/energy.

HallsofIvy
Dec3-10, 08:56 AM
Hello all,
If there are two planets of identical size but very different mass, why does one have a higher gravity than the other given that space/time is curved by each in the same way? Or does space/time curvature depend not on the size of a body but its mass?
TIA
Mekon
Curvature depends upon "mass-energy". Where in the world did you get the idea that it depended on "size" (volume)?