Not magnetism. In full on GR you get gravitomagnetism - a gravitational analogue to magnetism. The author made use Of full on GR instead of a Newtonian approxi

Not magnetism. In full on GR you get gravitomagnetism - a gravitational analogue to magnetism. The author made use Of full on GR instead of a Newtonian approximation. I thought this was already known to be helpful?