What is the nature of the gravitational force?

[dimamuzhetsky]

2 separate matter particles attract each other physically.Why so?Please explain me the phenomena.Thank You

[jake-the-peg]

There are two explanations.

The first is Einstein's General theory of Relativity. In this matter causes space to curve and this curvature of space time causes the attraction.

This explains why massive bodies like the sun can cause mass-less light to bend around it. it also explains the deviation in Mercury's orbit and other phenomina which cannot otherwise be explained.

There is also a theory derived from the other force laws that explain Electromagnetic and the nuclear forces. In this a mass-less virtual particle called the graviton transmits the force between two bodies.

There is no evidence for this second theory yet - no one has found the graviton. The belief in it is because people think that gravity "should" work like all the other forces.

[vascop]

Jake
It's not the curvature of space-time that CAUSES the attraction. There is no need to postulate a force in this case because the way things move is BECAUSE of the curvature of space-time.

[Old_Geezer]

Maybe in a future more encompassing theory we'll find that curved space and gravitons are simply different ways of 'viewing' the same thing.

[jake-the-peg]

That is the hope OG of those looking for Grand Unifying theories.

We may however find that the relationship is more subtle - there are a lot of reasons for seeing Gravity as the Joker in the pack

True vascop - results would have been a better word

[Clanad]

Just a little fleshing out of previous answers... F=Gm1m2 / r2 states that gravity is proportional to the product of the two masses (m1 and m2), and inversely proportional to the square of the distance (r) between their centers of mass. (G) is the gravitational constant in this equation. Problem is that as distance increases, the force decreases but is still existant. Additionally, the force, whatever it turns out to actually be, acts at or near the speed of light (c)...

[beso]

The real question is .... Why does matter curve spacetime?

[TorahBoy]

Love is what holds matter together. Without love, we all fall apart in the end. Email me. [e-mail]