: : I suggest that there is no such thing as a "Graviton". : Gravity is not propagated by particles, but must rather be a "tidal force" resulting from a curvature of space-time.

You are correct in saying that gravity is not propagated by particles, but the thing is this doesn't mean gravitons don't exist. This is because if they did exist they would be like photons(i.e packets of gravity as opposed to packets of energy.). Also graviational attraction is a universal force effecting all matter, hence it is not that difficult to see that gravitational force is in fact a form of quantised energy which acts to bring matter together.

As to gravity be a tidal force resulting from the curvature of space-time: Gravity causes the curvature of space-time, so what you are saying in that the curvature of space-time causes gravity is that gravity causes gravity.