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automan
May22-11, 07:16 PM
Please forgive me if this is a basic question. I have no education past high school and this is my first post on this forum. I can only understand something if I can visualize it in my head... see the picture in my mind.

Can you describe the mechanism that makes an object in space not just move towards a massive object, but also accelerate towards it?
FtlIsAwesome
May22-11, 08:51 PM
Welcome to Physics Forums, automan! :smile:

Can you describe the mechanism that makes an object in space not just move towards a massive object, but also accelerate towards it?
Gravity?? I'm not quite sure what you're asking.
automan
May22-11, 09:08 PM
Yeah, I understand that gravity does it. I understand the Newtonian math involved and even how General Relativity describes it, but I don't fully understand the underlying mechanism. I understand the acceleration is measured by the inverse of the square of the distance, but I don't quite understand why.
FtlIsAwesome
May22-11, 09:48 PM
Ah. Hmm. Probably the only thing I can think of to describe it is "the curvature of spacetime". Its one of those things that are quite difficult to pin down at the source. Before Einstein, it was only thought of as an "unseen force acting at a distance", and seemed mysterious.

The inverse-square rule applies to other things as well, such as light, so I'd say its a property of space itself.


That's most of the thoughts I have on the subject. I'm a pretty much a noob, so someone else here might be able to offer you some insight.
automan
May22-11, 10:31 PM
I think there is a missing measurement in physics. One that describes a unit of space, not in terms of length, width, depth, but in terms of the space on a 4 dimensional plane. It's like gravity is a compression of space into a mass. The units of space around the compressed unit stretch towards the mass to fill in the void. It takes X amount of time for an object moving at a steady rate to pass through a unit of space, even if that unit is stretched towards a mass. This is what we view as gravitational acceleration towards a mass.
What do you think?