4 ms·
Isn't gravity a property of spacetime? (curvature)
by rkagerer 3y ago
Isn't gravity a property of spacetime? (curvature)
- petschge 3y agoYou can describe it that way. But different parts of spacetime can have different curvature, so you get different impact of gravity. No matter how you describe it, gravity is different on Earth, Moon or in deep space and your theory has to model that no matter if it uses forces, curvature of spacetime or something else.
- pdonis 3y agoMore precisely, tidal gravity is spacetime curvature. What most people think of as "gravity"--for example, feeling weight when you are standing on the surface of the Earth--is actually non-gravitational forces, such as the Earth's surface pushing up on you, that are keeping you from freely falling. If you are in free fall, the "force of gravity" as people normally think of it disappears. (This was the key insight that started Einstein on the path to General Relativity.) What is left over is tidal gravity--freely falling objects converging or diverging because of the geometry of spacetime.