a: Dual Pushing (anti graviton) gravity showing the speed of light created by transformed vacuum
strings after passing fermionic masses and shooting away as a counter act for the vacuum string pressure (Casimir effect) all around it.
b: The Solar instant gravity speed by local pressure of the oscillating string vacuum around the sun
(Tom van Flandern) The origin is assumed to be created by the vacuum polar pressure polarisation
inside each stellar system by SABHs ( Dual Stellar Achor Black Holes: former Herbig Haro systems)
c: The merger black hole lightspeed gravity waves found by LIGO, by local Planck length elongations
(redshift) variations around multiple black holes along the lightpath.
see also:
Emergent Gravity by Dipole Repeller Rigid String Pressure,
the Origin of Quantum Gravity and Non Inertial Black Holes.