I've split this from the giant battle dress thread as being OT.
Of course it exists, but it doesn't work the same way forces like electromagnetism do. Specifically, the idea that it exerts some force proportional to that other object's mass is a missunderstanding of how it works. It's an easy one to fall into though, after all it's what Newton thought and he was a true genius.
For gravity to cause an attractive force between objects, that attraction must be due to some property those objects share, and those properties must interact with each other. You might think that is mass, but that's not the case.
Massive objects warp the space around them and in turm that curvature of space affects objects moving through that space, but that influence on other objects has nothing to do with any properties of those objects. Specifically, it's independent of the mass of those objects. That's why gravity affects light which has no mass. If gravity actualy exerted an attractive force on objects the way magnetism does, the force of that attraction would be proportional to their mass. But as light has no mass, that attractive force would be zero. Yet light is affected by gravity. Therefore gravity can't be considered to be two masses acting on each other. QED.
Magnetism is an interation between two magnetic particles. It has no effect on particles that are not themselves magnetic, and the strength of the interaction is proportional to the magnetic charge of the particles involved. Gravity does not work like that at all. It is not an interaction between two particles with mass. Two massive particles do influence each other due to the fact that they both curve space, but the influence of one object on the other has nothing whatever to do with the other object's own mass, or even dependent on it having any mass whatsoever.
That's why saying something like "gravity affects the other object proportional to it's mass" is nonsense, whereas saying equivalent things about magnetism and electrical fields (or even the weak and strong nuclear forces) would make perfect sense. Gravity is fundamentally a different sort of thing.
Excellent advice.
Simon Hibbs
Reynard said:"Except that gravity is not really a force. Free floating objects in a gravitational field, such as falling objects or objects in orbit, expereince no acceleration and no forces."
Where in the world did you find that definition. Every source I found does call it 'gravitational force'. It causes attraction between objects, even light and imparts acceleration as part of attraction. Gravity exists! ...
Of course it exists, but it doesn't work the same way forces like electromagnetism do. Specifically, the idea that it exerts some force proportional to that other object's mass is a missunderstanding of how it works. It's an easy one to fall into though, after all it's what Newton thought and he was a true genius.
For gravity to cause an attractive force between objects, that attraction must be due to some property those objects share, and those properties must interact with each other. You might think that is mass, but that's not the case.
Massive objects warp the space around them and in turm that curvature of space affects objects moving through that space, but that influence on other objects has nothing to do with any properties of those objects. Specifically, it's independent of the mass of those objects. That's why gravity affects light which has no mass. If gravity actualy exerted an attractive force on objects the way magnetism does, the force of that attraction would be proportional to their mass. But as light has no mass, that attractive force would be zero. Yet light is affected by gravity. Therefore gravity can't be considered to be two masses acting on each other. QED.
Magnetism is an interation between two magnetic particles. It has no effect on particles that are not themselves magnetic, and the strength of the interaction is proportional to the magnetic charge of the particles involved. Gravity does not work like that at all. It is not an interaction between two particles with mass. Two massive particles do influence each other due to the fact that they both curve space, but the influence of one object on the other has nothing whatever to do with the other object's own mass, or even dependent on it having any mass whatsoever.
That's why saying something like "gravity affects the other object proportional to it's mass" is nonsense, whereas saying equivalent things about magnetism and electrical fields (or even the weak and strong nuclear forces) would make perfect sense. Gravity is fundamentally a different sort of thing.
Go read a book!
Excellent advice.
Simon Hibbs