The mechanism of gravity

There is no single magnetic poles existing, same as there is no single charged particles existing.

Why? Force and motion.

Suppose there are single magnetic poles, same poles will repel each other, opposite poles will attract each other. Therefore the smallest magnet is formed from two opposite poles. They must become one piece under attraction force. A magnet is neutrally magnetic charged, but it attracts other magnets, we call the force magnetic force.

Neutrally charged matters/atoms are formed from charged atom parts. All single charged parts must attract opposite charged parts under Coulomb's force, similar to single magnetic poles, 10^ 36 times must. Therefore the smallest particle is neutrally charged atom, but it attract other atoms, the source of gravity.  

Due to the geometry of the atom, charges are equally distribute at radius direction, so the net electrical charge close to zero, make it a weak attraction force between masses. Magnets two poles at opposite direction, therefore magnetic force is much stronger than gravity.

Cosmology has the weakest predictive success rate in science for a reason, no curiosity or scepticism. When you think about it, name one thing that is based on GR, or any evidence that backs it up? Millions of devices in the modern world in industry, engineering and tech work on principles of Newton, Faraday, Edison, Maxwell, Tesla etc. Real things that exist. Nothing real is based on GR so its useless. Probably because its garbage used to prop up the imaginary things in cosmology, they need to keep it alive, or they are dead. Dark matter, dark energy, creation miracles and black holes are gone, we just need to make sure that the unicorns in theoretical pseudoscience are not treated with to much respect and accountability is demanded. The two that need investigation for fraud are LIGO and EVENT HORIZON as a matter of urgency.

The smallest particle existing is hydrogen atom.