Do gravitational forces have to follow spacetime in the same way as light? Or does gravity act in a higher dimension?
It is. There's very good theoretical reasons and an absurd amount of experimental evidence for the speed of light being the universal speed limit.I can't say I've had the luxury of being able to focus on this area of physics, but I don't know if the speed of light is necessarily the universal speed limit.
Then those physicists don't know what they're talking about. Gravitational waves are required to travel at c by General Relativity. Traveling FTL would bring about some serious paradoxes.Some physicists believe gravity waves travel much faster.
If you mean the masses are two-dimensional masses on the surface of this sphere, then gravity would act along those two dimensions, not through the third dimension since it doesn't exist in this hypothetical scenario.Imagine you're world as a 2-sphere, and only two masses exist in it, and on opposite sides of the sphere. Would gravity's influence be able to travel the line connecting the two masses (moving in a dimension not described by the 2-sphere - i.e. force vectors pointing towards each other through the center of the sphere), or would the force vectors on the masses point tangent to the 2-sphere?