Could gravity be residual strong force?

[cuallito]

If nucleons are held together by residual strong force could could gravity be residual residual strong force reaching outside the atom, causing atoms to tend to clump together?

 

[javierR]

No, for one thing the theory of the strong interaction that we have says that the force strength drops off much too quickly, and this theory has been tested in enough detail to not doubt its validity from the largest distance scales to the smallest that we've probed. When you put a large number of atoms together, they don't increase the range of the strong interaction. On the other hand, the gravitational force has a "long range" so if you put many contributors (atoms) together to form e.g. a planet, you and other objects far away can feel the effects.