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I haven't done a ton of research on Gravitational Waves, but I have done some theorizing. Are these properties confirmed (by theory or observation) characteristics of GW?

  1. Gravitational Waves travel at the speed of light
    Reasoning: The observation of GW coordinated with the observation of the two black holes colliding. The observations of the collision were Electromagnetic, and inherently traveled at the speed of light (or pretty darn close). If the two sets of waves originated from the same point, and arrived at another point at the same time, then they must be traveling at the same average speed.

  2. Building on #1, Gravitational Waves have no mass
    Reasoning: If GW travel at the speed of light, they must have either infinite thrust or zero mass. Infinite thrust is unlikely, therefore we can conclude that they have zero mass.

  3. Also building on #1, the speed of Gravitational Waves can be manipulated
    Reasoning: It is well known that the speed of light varies according to the medium through which it travels. Could GW theoretically be slowed down by changing the medium through which they travel? If we could slow them down, would the effects of gravity be lessened, or merely delayed?



Am I correct in my thinking, or have I lost my mind?

Extra Credit: Using what we currently know about GW, could we build a gravity generator? TO CLARIFY: When I say gravity generator, I mean one powerful enough to hold a human to the deck of a spacecraft (not necessarily 1G though - could be as little as 0.1G).

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closed as off-topic by ACuriousMind, CuriousOne, John Rennie, Martin, Kyle Kanos Feb 17 '16 at 11:20

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If this question can be reworded to fit the rules in the help center, please edit the question.

  • $\begingroup$ ouch, why -5? Downvoters please leave a comment. $\endgroup$ – Daniel Feb 17 '16 at 1:50
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    $\begingroup$ I didn't downvote, but I suspect that the statement "I haven't done a ton of research on Gravitational Waves, but I have done some theorizing" is part of the problem. $\endgroup$ – march Feb 17 '16 at 4:14
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    $\begingroup$ Not my downvotes, but note that this site is, and I quote from the tour, a question and answer site for active researchers, academics and students of physics and astronomy. Non-physicists are welcome, but to post a question admitting that I couldn't be bothered to research this so I thought I'd ask here instead is not going to be well received. $\endgroup$ – John Rennie Feb 17 '16 at 6:59
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    $\begingroup$ I'm voting to close this question as off-topic because it shows insufficient prior research $\endgroup$ – John Rennie Feb 17 '16 at 7:00
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    $\begingroup$ Aha, I see how it is here. Well then, thank you for your 'help' $\endgroup$ – Daniel Feb 17 '16 at 14:27
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  1. Yes, it comes out of GR. I am not sure if the EM version of event is/was observed. I guess the time lag between two locations of LIGO indicates ~ light speed.
  2. No mass, they are ripples in space, so, they have energy.
  3. Most likely not. Their speed does not depend upon the medium.

  4. Yes we can make tiny ones based upon today's capabilities. Real challenge would be to build big enough gravity generator, and sensitive enough detectors.

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    $\begingroup$ There are no gravitational waves in SR. The assertion in 4 requires a strong reference or it should be removed. $\endgroup$ – Emilio Pisanty Feb 17 '16 at 0:48
  • $\begingroup$ I mean the tiny ones, for example when two cars run around one another accelerated. They won't be measureable $\endgroup$ – kpv Feb 17 '16 at 0:58
  • $\begingroup$ You mean Teensy-weensy-tiny-miny? Maybe. Now here is the things... when we do a resonant Cavendish experiment (in the near field), would we call that gravitational waves? $\endgroup$ – CuriousOne Feb 17 '16 at 1:37
  • $\begingroup$ Per wiki page " In certain circumstances, accelerating objects generate changes in this curvature, which propagate outwards at the speed of light in a wave-like manner. These propagating phenomena are known as gravitational waves". "certain circumstances" means asymmetrical movement. Can not dig into details, not an expert. $\endgroup$ – kpv Feb 17 '16 at 3:21
  • $\begingroup$ Why exactly do you say the waves have energy given that the stress energy tensor is zero? $\endgroup$ – Timaeus Feb 19 '16 at 19:41

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