There is something that I have always wondered but have never found in any of the popular science magazines or heard in a lecture. Is a gravitational field produced by mass or energy ?
In refering to the equation :
E^2 = (mc^2)^2 + (pc)^2
Is it the rest mass that produces a graviational field or mass combined with it's momentum ?
Does the relativistic mass generate a gravitational field which is also relative to the observer ? Is a stronger gravitational field generated as an object is accelerated from an observer as a result ? Does GR take this into account ?
