swansont Posted March 5, 2016 Share Posted March 5, 2016 Funny thing just about every site today has been saying KE is part of the mass, but not rest mass. I'll have to go through them again. What is the clue to understanding "KE never contributes to the mass...."? Already covered this, as does Mordred http://www.scienceforums.net/topic/93568-robittybobs-law-orbital-issue/?p=909132 1 Link to comment Share on other sites More sharing options...
Robittybob1 Posted March 5, 2016 Author Share Posted March 5, 2016 Would you agree with this statement "Inertial mass increases with speed, while gravitational mass does not."? I'm struggling with this one when I relate it back to the RB law. Weren't we saying that the rest mass increases as an object uses it kinetic energy to climb out of a gravity well? To measure gravitational mass wouldn't you need to pass it by another mass and see where it will orbit? Link to comment Share on other sites More sharing options...
Robittybob1 Posted March 6, 2016 Author Share Posted March 6, 2016 In one paper it likened Gravitational Waves to the water coming out of an "S" shaped rotating garden sprinkler. So I'd say there are two streams of water coming out continuously but when a person is standing closeby there are two showers of water per revolution of the sprinkler head. In the garden sprinkler the water is piped in but where does the "endless supply" of gravitational energy come from? Is it just the potential energy between the masses? No for some of that potential energy is converted to kinetic energy. So I have a feeling it will be 1/2 its PE. So was that "3 solar masses of energy released" equivalent to half the potential energy of 2 BHs (of the masses specified)?They say this energy was released "mostly in the final moments". That would be true of PE as well wouldn't it? Link to comment Share on other sites More sharing options...
swansont Posted March 6, 2016 Share Posted March 6, 2016 In one paper it likened Gravitational Waves to the water coming out of an "S" shaped rotating garden sprinkler. What paper? Link to comment Share on other sites More sharing options...
Robittybob1 Posted March 6, 2016 Author Share Posted March 6, 2016 (edited) What paper? It was one I was reading last night. http://w.astro.berkeley.edu/~gmarcy/astro160/papers/binary_black_hole_mergers.pdf http://w.astro.berkeley.edu/~gmarcy/astro160/papers/binary_black_hole_mergers.pdf [Can't copy it sorry] Edited March 6, 2016 by Robittybob1 Link to comment Share on other sites More sharing options...
swansont Posted March 7, 2016 Share Posted March 7, 2016 It was one I was reading last night. http://w.astro.berkeley.edu/~gmarcy/astro160/papers/binary_black_hole_mergers.pdf OK. It used the sprinkler and conservation of momentum to explain if there's a net force. Anything beyond that is taking the analogy too far. Link to comment Share on other sites More sharing options...
Robittybob1 Posted March 7, 2016 Author Share Posted March 7, 2016 OK. It used the sprinkler and conservation of momentum to explain if there's a net force. Anything beyond that is taking the analogy too far. There is a little more to it. They are saying during the ringdown phase there could be a net motion of the merging BHs the center of mass could start shifting in space and on merger the CoM drifting off. Now I'm only taking their word for that as I can't quite picture that happening ATM. Link to comment Share on other sites More sharing options...
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