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# Is Space Zero Gravity (0 G)

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I was describing a field, you obviously couldnt tell me what a field was as a field even is propagated at around c, you said "fields don't propagate". Obviously my citation shows otherwise. So I stuck with a field as a ripple in a pond, which is why I went on with "wave". It was actually my most recent article cited that made me change my terminology, "before hand it was thought to be impossible to measure the speed of gravity without gravity waves". Your definition was a bit misinformative, you should have taken a more Einstein approach, less Newtonian. That would have fit better with modern results.

I think you're being pretentious.

But that's just me.

No a field does not propagate.  A disturbance in a field propagates. That is what your linked article is saying. A string held tight by 2 people is just a string. If one person wiggles one end, a disturbance will propagate along the string. The disturbance is not the string.

This is the thing billvon and I have been pointing out to you from the beginning. A wave is a propagating disturbance in a field, of a periodic nature, which carries energy.

A static field is just there. It does not consist of anything being radiated, it carries no energy and it is emphatically not a wave.

Regardless of the other things you are obviously interested in, you must let go of your misconception about this if you are going to make any sense. I have suggested a couple of good Wiki articles that can help. I commend them to you once more.

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I was describing a field, you obviously couldnt tell me what a field was as a field even is propagated at around c, you said "fields don't propagate".

Fields don't propagate.  Fields are static.  That's why electro/magnetostatics are a separate topic from electro/magnetodynamics.

So I stuck with a field as a ripple in a pond, which is why I went on with "wave".

OK let's consider that example.  In that example, the pond with no ripples would be an example of a the static field.  The ripple would be an example of a dynamic wave that is propagating.

I think you're being pretentious. But that's just me.

Pretty funny coming from someone who thinks he is a "super polymath."

Edited by billvon
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No a field does not propagate. A disturbance in a field propagates. That is what your linked article is saying. A string held tight by 2 people is just a string. If one person wiggles one end, a disturbance will propagate along the string. The disturbance is not the string.

This is the thing billvon and I have been pointing out to you from the beginning. A wave is a propagating disturbance in a field, of a periodic nature, which carries energy.

A static field is just there. It does not consist of anything being radiated, it carries no energy and it is emphatically not a wave.

Regardless of the other things you are obviously interested in, you must let go of your misconception about this if you are going to make any sense. I have suggested a couple of good Wiki articles that can help. I commend them to you once more.

I think you like to make stuff up as you go along.

For instance, your story isn't matching up with OceanBreeze. You're describing a gravity wave and basically saying "only a gravity wave propagates", in the second article I cited it said gravity was propagating from Jupiter without gravity waves, and OceanBreeze said we can't measure gravity waves in anything smaller than a neutron star as well,& Jupiter is smaller than a neutron star.

"No one had tried to measure the speed of gravity before because most physicists had assumed that the only way to do so was to detect gravitational waves," Kopeikin recalled. However, in 1999, Kopeikin extended Einstein's theory to include the gravitational effects of a moving body on light and radio waves. The effects depended on the speed of gravity."

Regardless I go with the more credible sources. & I trust Harvard.edu over wikipedia.com.

electro/magnetostatics are a separate topic from electro/magnetodynamics

okay, other than sharing the inverse square law, electrons=/=gravity.

Edited by Super Polymath
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For instance, your story isn't matching up with OceanBreeze. You're describing a gravity wave and basically saying "only a gravity wave propagates", in the second article I cited it said gravity was propagating from Jupiter without gravity waves, and OceanBreeze said we can't measure gravity waves in anything smaller than a neutron star as well,& Jupiter is smaller than a neutron star.

You're getting confused here.  There is a GRAVITY FIELD (static) from Jupiter.  We know this because we can see how it deflects the courses of Jupiter's moons and our own spacecraft.  We can also see how it deflects the light from distant stars.  There are also GRAVITY WAVES (dynamic) that propagate from Jupiter due to its motion, but are too small for us to detect.

okay, other than sharing the inverse square law, electrons=/=gravity.

And a pond =/= vacuum.  But you were OK using that example.

Also, why bring up electrons?  No one was talking about elementary particles.  Are you starting another topic?

Edited by billvon
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I think you like to make stuff up as you go along.

For instance, your story isn't matching up with OceanBreeze. You're describing a gravity wave and basically saying "only a gravity wave propagates", in the second article I cited it said gravity was propagating from Jupiter without gravity waves, and OceanBreeze said we can't measure gravity waves in anything smaller than a neutron star as well,& Jupiter is smaller than a neutron star.

"No one had tried to measure the speed of gravity before because most physicists had assumed that the only way to do so was to detect gravitational waves," Kopeikin recalled. However, in 1999, Kopeikin extended Einstein's theory to include the gravitational effects of a moving body on light and radio waves. The effects depended on the speed of gravity."

People with physical science degrees do not generally need to make physical science up. It is true that GR was not part of my degree studies, but I can read a physics article and understand it, especially when the analogies with electromagnetic fields (which I did study) are strikingly obvious. Billvon and I have been saying the same thing consistently from the beginning. And I've given you the references for you to check for yourself, so rather than trying to belittle me as a fantasist why not read them yourself and then we can talk some more?

If you refuse to read them and prefer to wallow in ignorance, that is your affair of course. But you will find - indeed, are already finding - that some of the other things you say, which are derived from this misconception of yours, meet with disagreement and ultimately ridicule. You have the chance to learn from your postings on this forum, as we all do. For instance I now know about Lagrangian points, which I did not before (I do think the contour diagram is elegant) :)

Now about Jupiter and your article, as I said before, what it is talking about is the disturbance in the field due to the accelerative motion of Jupiter as it orbits. This disturbance will travel out from Jupiter at the speed of light. But that does not mean that gravity is made of waves. Can you not see the difference here? Think of my string analogy or billvon's ripple on the pond.

But look here, I've found a better article here on the subject that exactly addresses what we have all been talking about: https://en.wikipedia.org/wiki/Speed_of_gravity

This makes exactly the distinction between static fields and waves that we have discussing. Please, if you do nothing else, read this article, especially the section on static fields and motion before you make any more posts on this topic.

Edited by exchemist
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Now about Jupiter and your article, as I said before, what it is talking about is the disturbance in the field due to the accelerative motion of Jupiter as it orbits. This disturbance will travel out from Jupiter at the speed of light.

Yeah, that's totally what the article said.

But look here, I've found a better article here on the subject that exactly addresses what we have all been talking about: https://en.wikipedia.org/wiki/Speed_of_gravity

This makes exactly the distinction between static fields and waves that we have discussing. Please, if you do nothing else, read this article, especially the section on static fields and motion before you make any more posts on this topic.

Tsk tsk. Another Wikipedia.

Static fields was one of over 5 different models for gravity in that article, all of which predate the test in the .edu I hyperlinked, read the "Lorentz-Poincare" model in that article. Fits better with modern results.

Edited by Super Polymath
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I think you like to make stuff up as you go along.

For instance, your story isn't matching up with OceanBreeze. You're describing a gravity wave and basically saying "only a gravity wave propagates", in the second article I cited it said gravity was propagating from Jupiter without gravity waves, and OceanBreeze said we can't measure gravity waves in anything smaller than a neutron star as well,& Jupiter is smaller than a neutron star.

"No one had tried to measure the speed of gravity before because most physicists had assumed that the only way to do so was to detect gravitational waves," Kopeikin recalled. However, in 1999, Kopeikin extended Einstein's theory to include the gravitational effects of a moving body on light and radio waves. The effects depended on the speed of gravity."

Regardless I go with the more credible sources. & I trust Harvard.edu over wikipedia.com.

I don't see any points of contention between what I said and what exchemist is saying.

As for that experiment you keep mentioning, I don’t understand it at all. It seems to me all they are measuring is the speed of the photons passing through the gravity field of Jupiter; in other words, they were measuring the speed of light, not gravity!

I will need to see a much better explanation of what they did.

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I will need to see a much better explanation of what they did.

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Thanks. I will have a look and get back to you.

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Hmmm. The link you gave is to a rebuttal of the experiment!

Is that what you intended to link to?

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Hmmm. The link you gave is to a rebuttal of the experiment!

Is that what you intended to link to?

Its a peer review with counter arguments, it covers the article more thoroughly.

Doesn't disprove anything, use it to help you understand. It critiques a bit.

Edited by Super Polymath
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Its a peer review with counter arguments, it covers the article more thoroughly.

It helps me to understand alright!

That paper says almost exactly what I said:

Since the difference between θobs and θ1 is due to the change in the position of

Jupiter as the quasar’s radio waves propagate from Jupiter to Earth, it is clear that

the parameter c in Eq. (1.5) is the speed of light and has nothing to do with the speed

of gravity. Therefore there was no justification in using cg in lieu of c when expressing

the leading term in terms of θ1.

The measurement of Fomalont and Kopeikin of the Shapiro time delay due to

Jupiter is a remarkable experimental achievement. One should remember that the

non-Newtonian effects of general relativity due to a planet had hitherto never been

detected. However, the experiment has little theoretical significance or fundamental

importance, and it indicates nothing about the speed of gravity.

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Both reviews speak of gravitational propagation without gravity waves, which contradicts both of you.

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Both reviews speak of gravitational propagation without gravity waves, which contradicts both of you.

Exactly.  Static gravity fields can "propagate" (it's not the correct word, but let's go with it) without gravity waves.  Once again:

There are gravity fields (static) that arise from mass.  We know this because we can see how this field deflects the course of objects and light.

There are also gravity waves (dynamic) that propagate through space that arise from accelerating/decelerating mass.

And it is what we've been saying for several pages now.

Edited by billvon
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There are also gravity waves (dynamic) that propagate through space that arise from accelerating/decelerating mass.

No, there aren't Edited by Super Polymath
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Since LIGO started operating, two discrete events have been observed.  They have been theorized for a long time, and we finally have data that shows they exist.

From LIGO:

On February 11, 2016, the LIGO Scientific Collaboration and Virgo Collaboration announced the first confirmed observation of gravitational waves from colliding black holes. The gravitational wave signals were observed by the LIGO's twin observatories on September 9, 2015.

On June 15, 2016, the LIGO Scientific Collaboration and Virgo Collaboration announced the second confirmed observation of gravitational waves from colliding black holes. The gravitational wave signals were observed by the LIGO's twin observatories on December 26, 2015.
Edited by billvon

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