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[a500lbgorilla]

How do force carriers physically work?

Use Gravity and orbits as an example. If I'm the ISS how am I exchanging force carriers with the Earth and vice versa?

[MadMojoMonkey]

How do force carriers physically work?

Use Gravity and orbits as an example. If I'm the ISS how am I exchanging force carriers with the Earth and vice versa?

Gravity is not explained in terms of force carriers. The hypothetical force carrier for mass is called the graviton. It is hypothetical because no graviton has ever been observed. The link between Quantum Mechanics and General Relativity is still not understood.

Gravitation is the motions of large bodies
Gravity is the force which causes said motion
A Graviton is the force carrier of mass which imparts gravity interactions and causes gravitation.

I can do this for anything BUT gravity and orbits. The problem with gravity and orbits is that the hypothetical graviton has never been observed. There is reason to suspect that there might be another explanation for the way gravitation is caused. Recall that Einstein's General Relativity states what appear to be ellipses are really straight lines in curved space-time.

If you had a trampoline, and you took some point on the mat (call it the center) and pulled it down, the mat would have a curved surface similar to the bell on a tuba. (I have no idea if these curves are similar mathematically, but they look so visually). Now put a marble on the mat and push it in any direction except for directly toward or away from the center. If the push was less than the "escape velocity" and somehow there is no friction and the mat is large enough to contain the entire path, then the marble will roll in an elliptical "orbit" forever.

Now imagine that what appears to be empty space is, in fact, curved like that mat. Instead of a plane that is warped out of form into a third dimension, space-time is a volume (really, it's 4-dimensional, so volume is still not the right word) that is warped out of form into some higher dimension(s).

This visualization illustrates the description offered by General Relativity. The problem is that it really fails. In the example, there is an external force (gravity) acting on the marble, and in space-time the curvature is enough. This really bothers me, but I don't have a better analogy.

Next post: Virtual Particles and the exchange of forces.

Here is a link to a great FAQ about this topic. I will probably say much the same in my next post.