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Thought experiment: Imagine the sun suddenly disappeared; lets say it some how transported to the edge of the observable universe.What will be the effects on the space-time?

(1) What does General Relativity (specifically) have to say about the disappearance of mass from the portion of space-time being analyzed?

I predict that the space will oscillate ,like a spring; interacting with it self (assuming the mass was spherical, and did not cause a force to act upon space in any direction), until it dampens out due to the interference, and initial "springiness" of space.But I do not know, I am no GR specialist.

(2) Can someone also tell about what will happen if the opposite happened, (a mass suddenly appeared)?

HDE 226868
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Numoru
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    The sun can't just suddenly disappear. What you're asking us to do is use the laws of physics to describe a situation that violates the laws of physics. – Jold Sep 07 '14 at 20:40
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    GR has nothing to say about the disappearance of mass. That's a matter of energy conservation, which won't let it happen. What would happen if mass would disappear can be predicted using general relativity. That prediction would, of course, be completely nonsensical, since it would describe a non-physical process. It can therefor not be tested experimentally and would not be science. – CuriousOne Sep 07 '14 at 20:43
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    Aside from the goods points raised, why would space oscillate? By the way, I just noticed the gravitational waves tag. Why would you think those play into it? – HDE 226868 Sep 07 '14 at 20:48
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    possible duplicate of The speed of gravity? – David Hammen Sep 07 '14 at 20:52
  • I'm not putting this as an answer because I've not read it properly myself yet, but there is an article at http://www.mathpages.com/home/kmath585/kmath585.htm with a very suggestive title, and it goes into excruciating detail about just this subject. Perhaps one of the experts around here could look it over? – m4r35n357 Sep 07 '14 at 20:55
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    I marked this as a possible duplicate because that linked question asks what would happen if the Sun disappeared, which is exactly what this question asks. – David Hammen Sep 07 '14 at 20:56
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    Short answer to this question: GR can't answer this question. Mass-energy can't suddenly disappear because mass-energy is locally conserved in GR. This question (and the linked question) are essentially asking "What does general relativity predict will happen when general relativity is violated?" These kinds of questions don't make sense. – David Hammen Sep 07 '14 at 20:58
  • I agree that it is a duplicate simply because "The speed of gravity" seems to be the only thing that relates to this question that could be answered. On a positive note, Numoru, The Scientific Imagination proposal might take this question, though, and I've already put a link there to this question. It fits there better than here - just look at the comments here. – HDE 226868 Sep 07 '14 at 21:01
  • @m4r35n357 (could you have picked a username that is harder to type? :-)), while I am by no means an expert, the page seems to reference the speed of gravity, just like David Hammen did. – HDE 226868 Sep 07 '14 at 21:05
  • I dont care if the sun is the specific mass that disappears. My question is on the reaction of spacetime if any mass were to "disappear". And for the thought experiment, will it be so hard to scale up properties of virtual particles, (not saying this is physically possible),in order to think about this. – Numoru Sep 07 '14 at 22:59
  • @Numoru: You need to accept "yes" for an answer. In this case "Yes, it is completely nonsensical to expect any theory to predict something useful about what would happen if something unphysical is stuffed into its guts.". That's not how physics, and science in general, work. As for virtual particles: if you were to apply a classical field theory like GR to them, the vacuum would be unstable, just like normal atoms would be unstable, if classical electrodynamics would be the correct description of the electromagnetic field. It's not, and neither is GR at the quantum level. – CuriousOne Sep 08 '14 at 00:00
  • @Numoru, as HDE226868 has told you, Scientific Imagination is a better place for these kind of questions. It's just a proposal yet, but you have somewhere to post it. – sampathsris Sep 13 '14 at 14:15

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