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LIGO and speed of gravitational waves

  1. Jun 29, 2004 #1
    LIGO may have failed to detect gravity waves because they move faster than light and so have a greater wavelength than expected and probably a lower amplitude too.
  2. jcsd
  3. Jun 29, 2004 #2
    Gravitational waves "effect" speed of light. :confused: How would you explain gravitational lensing?

    The standard view of the space time fabric reveals mass can warp that fabric.

    Hulse and Taylor were very specific in regards to the energy released from the rotation. So these gravitational waves take something with them and the photon is effected by it?

    Strong energy congregations also warp space. If photon is held to localized event, then I guess you would have to understand the evolution to the Weber bar? :approve: ?
    Last edited: Jun 29, 2004
  4. Jun 29, 2004 #3
    The energy of the waves is still the energy that Ligo predicts for them.
    The amplitude would be smaller though.
  5. Jun 29, 2004 #4
    Maybe I am confusing things here.

    It is known that from predictions of GR that gravitational waves can go through anything.

  6. Jun 29, 2004 #5
    The amplitude would be smaller because to have the same energy a wave of greater wavelength would need to have smaller peaks.These waves still pass through anything.

    If Weber did detect those oscillations SIMULTANEOUSLY at 1000km separation
    then he must have been right about their origin.

    Why are the laser beams bounced back and forth so many times?
  7. Jun 29, 2004 #6
    As in post above

    There were difficulties with the bars in terms of resonance and problems of earth's interference. I'd have to double check.

    Last edited: Jun 29, 2004
  8. Jun 30, 2004 #7
    Gravity waves squeeze masses together and pull them apart.
    Are they two waves with different polarities?
  9. Jun 30, 2004 #8


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    The change in distance between the two arms of the experiment is very slight, and therefore hard to detect. For this example, let's use a change with a negative value; a contraction which decreases the distance between the two arms. Let's assume that the original distance between the two arms is 1000. Never mind "1000 whats?", the unit of measure does not matter, but let's assume that in this unit of measure, "one" represents the amount of change that the sensor is capable of detecting. If we simply send a beam straight across from one arm to the other, and a gravity wave passing by decreases the distance between the two arms .1, then the total length of the laser was originally 1000, and it has been shortened by .1, which is too little to detect.

    However, if we bounced a beam back and forth between the two arms about 100 times, the total length of the beam is 100,000. When the distance between the two arms is decreased, the laser takes a trip that is .1 shorter each time it crosses between the two arms. After 100 trips, the laser's total distance traveled is shortened by a factor of 10 units of measure, which is easily detectable.
  10. Jun 30, 2004 #9
    So the compression would last for at least 10^ - 5 seconds?
  11. Jun 30, 2004 #10
    Sometimes it is confusing thinking aboiut tipping lightcones, but to have considered the photon being held to the brane( an event that has happened) and to see that the gravitational waves are not limited? They can leave to the bulk.

    This might not make sense, but if it does, maybe someone can answer from that perspective.

    The clarification on flexiing tubes of LIGO helps clarify things greatly, but has not answered Glast :smile:
  12. Jul 3, 2004 #11
    It will be unsuccessful until then the essence of gravitation will be understood.
    Application of concept " propagation" for gravitation is the main mistake.
    Propagation and gravitation are an opposite consepts.
    It is possible to apply them with attachment “anti” for one relative another.

  13. Jul 3, 2004 #12
    Let's focus on this then.

    I might have some problems understanding from the persepctive Taylor's demonstrations?

    From Mercury and the Daisey we learn to graduate to higher defintions with Taylor and Hulse.

    This information had to be going somewhere? :smile:

    Gravitatinal Radiation

    Last edited: Jul 3, 2004
  14. Jul 3, 2004 #13
    In the first - it is a drama of bygone days (some millions or billions years).
    You can’t to do the conclusions about this one today.
    In the second- it is not bad to have an own opinion except quoting.

  15. Jul 3, 2004 #14
    It is obvious I am not comprehending something you are, why I set the stage for you to speak further. The question is still out there and I wanted to show that from this point I would need some clarifications from you to understand your statements.

    Are you saying LIGO is failure because of the statements you are supplying?

    So please go ahead and I'll add coments after. By what I respond, you will know if I understood.

  16. Jul 4, 2004 #15
    I only want to say here, that experiments based on incorrect representation about an object of researches, can’t be successful.
    I try to show my vision of this problem in my threads "Dimensions", “ What is a force? ” and others. Agree, I can’t begin all over again in each thread of a forum. Therefore I invite you and other participants there for the further discussion.

  17. Jul 4, 2004 #16
    Gravity waves like light could be transverse waves that propagate through the ether at speed c.
    However, an event such as supernova may cause longitudinal waves that propagate through the ether. It is likely that these will travel 10 times (or more) the speed of light and be undetectable by LIGO equipment.
    Last edited: Jul 4, 2004
  18. Jul 4, 2004 #17
    Gravitation does not need in traveling. It is an action itself. Note the speed of light is absolute and single speed existing at microlevel.

  19. Jul 5, 2004 #18
    True. But if the gravitational effect changes because of some distant event, it does so at the speed of light, hence the gravity wave idea.
  20. Jul 5, 2004 #19
    Yes, locally gravitation attracts with a speed of light. This is a process of attraction itself. But globally there is no delay at all to start this attraction.
    It exist always and everywhere.

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