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Author Topic: Gravity waves, which way is up? Will LIGO experiment ever be able to answer?  (Read 752 times)

Offline JoeBrown

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The LIGO experiments have shown that gravity waves propagate at the speed of light.

So there's an energy transmission, but what direction, can the experiment prove one way or the other?

One might jump to the conclusion that gravity waves akin to light waves are emitted from a mass, but what if it's actually the opposite and instead its the fabric of space-time being sucked in?

The force sucks, like we all more or less understand, would that not suggest the waves are in effect pulling as opposed to pushing?

Seems like LIGO is the natural progression of the Michelson-Morley experiment...  Perhaps the aether debate need to continue.
« Last Edit: 21/03/2016 18:38:49 by JoeBrown »


 

Offline evan_au

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Quote
The force sucks, like we all more or less understand...
This is talking about static gravitational fields - "gravity sucks".

Quote from: JoeBrown
The force sucks, like we all more or less understand, would that not suggest the waves are in effect pulling as opposed to pushing?
The waves are not a static gravitational force, they are a propagating oscillation, spreading out from the source.

According to Einstein, they do not push or pull in the direction of propagation (that is a longitudinal wave), but they sort of wobble and twist at right angles to the direction of propagation.

But once the wave passes, matter returns to its original position, so overall they have not been pushed or pulled.

The waves do not suck, nor do they blow - they sort of hum...
 

Offline JoeBrown

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I think you have to admit, LIGO detectors are nearly identical the Micheson-Morley experiment on a much grander scale with a tweaked set of parameters.

The original set out to detect Earth's orbit through the aether.  For LIGO it took a couple of black holes ~60 times the size of our sun, 1.3billion light years away to set it off.

Seems there is an underlying fabric to space-time, evidenced by gravity waves. 

Isn't an oscillation both a push and a pull.  Herrumph.  Now I am confused.
« Last Edit: 21/03/2016 22:11:36 by JoeBrown »
 

Offline Colin2B

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Isn't an oscillation both a push and a pull. 
Depends on the type of oscillation as Evan says.
Sound is longitudinal, push pull; light is transverse - at right angles to propagation, in 2 directions, a dipole; water wave is sort of both - circular motion; but Grav wave is transverse in 4 dimensions (space + time) and is actually a quadruple  - I have real difficulty visualising it, but it's effect is a flexing of space in 2 directions simultaneously perpendicular to direction of travel, one out the other in and back again. 
 

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