What causes gravity?
GR's gravitational model is incomplete in another major aspect. There is no mechanism by which gravitation arises. The curved space-time model works for simple systems (like the solar system), but it falls apart on galactic (and larger) scales. Also, curved space-time is incompatible with the flat fields of quantum physics, which prevents the extension of gravitation to small scales.yogi said:In Einstein's theory (General Relativity) matter conditions local space which Einstein regarded as a continuum. It has met every test so far, but it is incomplete in one major aspect - it does not predict what the Gravitational constant is - this factor must be put into the equations by hand - it is determined from experimental measurment, not from theory.
Let's put the space-time curvature aside for now. I think what you are asking is what force keeps our feet planted on the ground (you know that it's gravity) and why is that so.afton said:What causes gravity?