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Questions on gravity

  1. May 22, 2009 #1
    What is the wavelength and frequency of gravity wave?

    Does gravity wave theoretically have properties that EM waves exhibits? - like diffraction, interference?

    If a mass suddenly converted to all energy, (E=mc2), what happens to the gravity waves that is already propagated? Wherever the gravity waves reach, it would still act on any other mass, regardless of the initial mass that originated the gravity exists or not. Right?
  2. jcsd
  3. May 22, 2009 #2
    At the moment Gravity Waves are a hypothetical construct so there wavelength and frequency are not known.
    You might like to try googling LIGO or this link if it works .http://www.ligo-la.caltech.edu/contents/overviewsci.htm [Broken]
    Which will tell you much more.
    Last edited by a moderator: May 4, 2017
  4. May 22, 2009 #3
    given that gravity is all things attracted to all things, should not all matter eventually be scattered evenly across space time, a kind of equilibrium of gravity; or is it impossible for this to occur in 3 dimensions as matter at the centre of the universe would experience differing gravity to matter not in the centre?
  5. May 24, 2009 #4
    A gravity wave will have a frequency which will depend on its source. If the gravity waves are created by two slow moving binary stars, they will have a low frequency, while it they are fast moving, it will have a high frequency. This is simply because the time taken to create each wave would have changed.

    I imagine that gravity waves would interfere with each other in the same way as normal waves. If two masses suddenly appeared either side of you, created a gravity wave, and then disappeared, then when the two waves reached you, they would 'cancel out' to give a very low overal gravitational pull. However if they suddenly appeared at about the same place, the waves would 'add up' and give a larger gravitational pull when they reached you.

    I dont think they would diffract though. Diffraction happens when waves hit obstacles, and gravity waves just dont really interact with anything. If one hit the earth, it would travel straight through it and be pretty much unaffected when it came out the other side.

    Gravity waves act more like longitudinal waves rather than transverse waves (like EM waves. They cant be polarised or anything. Gravity waves travelling through spacetime seem to me to be pretty similar to sound waves travelling through air.
  6. May 24, 2009 #5
  7. May 24, 2009 #6
    But, there is a point where the now vacant original mass no longer influences close to the vacant source. The rate of collapse is c.
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