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Author Topic: Would gravitational waves really be Lorentz invariant?  (Read 3345 times)

Offline jeffreyH

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As the assumed cause of time dilation, length contraction and attraction we assume gravitational waves move at c. Therefore these gravitational waves then affect themselves via self-interaction. This would require the field lines to intersect and would indicate an incoherence in the field. While this seems a reasonable assumption we impart a partially recursive function to gravitation. If magnetic field lines are not allowed to cross and therefore break the circulation of the flux how do we really know that gravitational field lines cross each other? Since the calculations all refer to the centre of gravity then the density of all field lines at a set radial distance must have a normal distribution. How does this then square with variation of mass density and still have the equivalence principle hold true?


 

Offline jeffreyH

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Re: Would gravitational waves really be Lorentz invariant?
« Reply #1 on: 28/09/2014 15:51:03 »
I am currently thinking about the far field distribution so may modify my views on this.
 

Offline jeffreyH

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Re: Would gravitational waves really be Lorentz invariant?
« Reply #2 on: 28/09/2014 16:16:10 »
It may be worth taking a look at this page. I am assuming the simulations are using numerical relativity.

http://www.einstein-online.info/spotlights/gowdy_st
 

Offline PmbPhy

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Re: Would gravitational waves really be Lorentz invariant?
« Reply #3 on: 29/09/2014 03:24:15 »
Quote from: jeffreyH
As the assumed cause of time dilation, length contraction and attraction we assume gravitational waves move at c.
Hi Jeff. You make a lot of strange comments here. I'll tackle them one at a time. First this one. Why do you phrase this statement like this? What does it all mean? What is the assumed cause of time dilation? What attraction are you referring to?

Quote from: jeffreyH
Therefore these gravitational waves then affect themselves via self-interaction.
Please explain what you mean by "these" gravitational waves affecting themselves by "self-interaction." What self interaction are you referring to?

Quote from: jeffreyH
This would require the field lines to intersect and would indicate an incoherence in the field.
Why?

Quote from: jeffreyH
Since the calculations all refer to the centre of gravity then the density of all field lines at a set radial distance must have a normal distribution.
Why?
 

Offline jeffreyH

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Re: Would gravitational waves really be Lorentz invariant?
« Reply #4 on: 29/09/2014 18:21:21 »
Quote from: jeffreyH
As the assumed cause of time dilation, length contraction and attraction we assume gravitational waves move at c.
Hi Jeff. You make a lot of strange comments here. I'll tackle them one at a time. First this one. Why do you phrase this statement like this? What does it all mean? What is the assumed cause of time dilation? What attraction are you referring to?

Quote from: jeffreyH
Therefore these gravitational waves then affect themselves via self-interaction.
Please explain what you mean by "these" gravitational waves affecting themselves by "self-interaction." What self interaction are you referring to?

Quote from: jeffreyH
This would require the field lines to intersect and would indicate an incoherence in the field.
Why?

Quote from: jeffreyH
Since the calculations all refer to the centre of gravity then the density of all field lines at a set radial distance must have a normal distribution.
Why?

Sorry Pete I am too tired to answer this at the moment but I will later.
 

Offline jeffreyH

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Re: Would gravitational waves really be Lorentz invariant?
« Reply #5 on: 30/09/2014 19:46:22 »
Pete I would just ignore the whole question. I do not have enough knowledge of what I am trying to ask. I need to do more reading before I can ask a proper question on this. I am about 75% through reading a book on Maxwell's equations so I was focusing on that more than gravitation. I am not surprised you didn't understand what I was going on about. I have been reading up on numerical relativity too and how theory predicts the event horizon moving outwards from at the centre of gravity. I would be interested on your views on this.
« Last Edit: 30/09/2014 19:49:01 by jeffreyH »
 

Offline PmbPhy

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Re: Would gravitational waves really be Lorentz invariant?
« Reply #6 on: 01/10/2014 05:54:37 »
Re: Would gravitational waves really be Lorentz invariant?

Yes. Any quantity which is moving at the speed of light is moving at an invariant speed. It makes no difference what is moving at that speed. In fact the term Lorentz invariant refers not to a physical object but with a mathematical quantity. So gravitational waves are not Lorentz invariant. It's their speed that is.
 

Offline ScientificSorcerer

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Re: Would gravitational waves really be Lorentz invariant?
« Reply #7 on: 04/10/2014 19:27:17 »
I know that gravity waves were predicted by Einstein but haven't quite been proven despite a lot of good research on the subject.  I'm confident that they do exist but I have a question to ask you about gravity which relates to the twisting of space.

Imagine a massive object like say earth with a gravitational field and you spin the massive object so the gravitational field will begin to twist slightly.

If normal gravity is made up of gravity waves like you suggest, which propagate outward or inward at "c" then how would that effect the twisting action of the spinning gravitational field?
 

Offline jeffreyH

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Re: Would gravitational waves really be Lorentz invariant?
« Reply #8 on: 05/10/2014 02:44:42 »
I know that gravity waves were predicted by Einstein but haven't quite been proven despite a lot of good research on the subject.  I'm confident that they do exist but I have a question to ask you about gravity which relates to the twisting of space.

Imagine a massive object like say earth with a gravitational field and you spin the massive object so the gravitational field will begin to twist slightly.

If normal gravity is made up of gravity waves like you suggest, which propagate outward or inward at "c" then how would that effect the twisting action of the spinning gravitational field?

Gravity probe B data showed evidence of the vortex around the earth predicted by Einstein. I have no idea what the profile of the field would be at the moment. Where would you start? The waves are hypothetical without direct evidence.
 

Offline PmbPhy

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Re: Would gravitational waves really be Lorentz invariant?
« Reply #9 on: 05/10/2014 04:50:37 »
Pete I would just ignore the whole question. I do not have enough knowledge of what I am trying to ask. I need to do more reading before I can ask a proper question on this. I am about 75% through reading a book on Maxwell's equations so I was focusing on that more than gravitation. I am not surprised you didn't understand what I was going on about. I have been reading up on numerical relativity too and how theory predicts the event horizon moving outwards from at the centre of gravity. I would be interested on your views on this.
You're an impressive man, Jeff! :)
 

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Re: Would gravitational waves really be Lorentz invariant?
« Reply #9 on: 05/10/2014 04:50:37 »

 

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