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# Is Space Zero Gravity (0 G)

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By very definition, a gravitational field is an effect of a gravitational wave; the imprint a body makes on the web of space-time. I claimed that the langrangian points were the effects of gravitational waves, not that they were the gravitational waves themselves....

[snip]

..... the cornucopia of citation should cement that I knew what I was talking about.

No, that is completely wrong. Billvon has had a go at explaining this to you, but let me try as well:-

Think of the electric field around an electric charge.  That is a static field: its values at any point in space do not vary with time. This static electric field transmits no energy. No wave is being propagated from the charge.

Now think of a dipole antenna. This has oscillating electric charges and it radiates an oscillating electric field (an oscillating magnetic field also arises at right angles to the electric field, due to the connection between electricity and magnetism, but that doesn't affect the analogy.) We call this an electromagnetic wave. This radiation carries energy away from the antenna.

Gravitation is just the same. A body with mass is surrounded by a static gravitational field. No radiation, no energy transmission, no waves. (Thinking about energy makes this obvious: if a wave were being propagated it would carry away energy, so the mass would lose energy over time. Where would this energy come from - what energy source in the body would be thereby depleted? It makes no sense.) If you want to think of it in terms of relativity, the curvature of spacetime is not changing: it has a fixed shape. No waves.

Gravitational waves are postulated to occur when there is a movement of mass, creating a sudden alteration in the strength of the gravitational field at some point in space. It is postulated that this change in gravitational field should travel outwards from the source of the disturbance at the speed of light, constituting a "gravitational wave".

Edited by exchemist

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No, that is completely wrong. Billvon has had a go at explaining this to you, but let me try as well:-

Think of the electric field around an electric charge. That is a static field: its values at any point in space do not vary with time. This static electric field transmits no energy. No wave is being propagated from the charge.

Now think of a dipole antenna. This has oscillating electric charges and it radiates an oscillating electric field (an oscillating magnetic field also arises at right angles to the electric field, due to the connection between electricity and magnetism, but that doesn't affect the analogy.) We call this an electromagnetic wave. This radiation carries energy away from the antenna.

Gravitation is just the same. A body with mass is surrounded by a static gravitational field. No radiation, no energy transmission, no waves. (Thinking about energy makes this obvious: if a wave were being propagated it would carry away energy, so the mass would lose energy over time. Where would this energy come from - what energy source in the body would be thereby depleted? It makes no sense.) If you want to think of it in terms of relativity, the curvature of spacetime is not changing: it has a fixed shape. No waves.

Gravitational waves are postulated to occur when there is a movement of mass, creating a sudden alteration in the strength of the gravitational field at some point in space. It is postulated that this change in gravitational field should travel outwards from the source of the disturbance at the speed of light, constituting a "gravitational wave".

Apparently you werent aware that every mass in the universe moves. *facepalm

What I said was that these lagrangian fields/waves are generated by gravitational fields/waves, and they are, are they not?

Given they're produced by the gravity of large bodies like those of the sun & earth, or the sun & the moon, as the link text says, which are all moving through space orbiting the sun or the sun circling the Milky Way & therefore are generating gravitational waves to form the gravity fields of Lagrange points-which themselves do not stay set, they orbit the sun and will release gravity waves just like everything else.

Not only are waves postuled to move at c, but they're also tested.

Edited by Super Polymath
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What the hell are you on about? Lol

Look it up.  Those are the definitions of the words you are using.

Well yeah, even past the particle horizon there are the gravitational waves and photons of other stars. But the 1/R^2 of earth's gravitational range will never make it there, thus the causal disconnect.

The gravity of the matter that made up the Earth IS ALREADY THERE.  Just as the light from the very early universe (the CMBR) IS ALREADY HERE.

Yes there is! The universe has expanded exponentially we have no idea what's become of the CMB blobs that are outside of the observable universe.

Once again, we are not seeing the CMBR because it came here from the edge of the Universe an hour ago.  An hour ago it was ALREADY HERE, well within our Solar System.  A year ago it was still closer to our Sun than to any other star.  Even though the event that caused that radiation is no longer connected to the universe, we are still seeing the light.

You seem to not understand this.  Let's try a simple example:

Let's say you are waiting for your bags to come out of the conveyor at the airport.  It takes forever to unload the plane, and the belt is slow.  In fact, the plane might have taken off again while you are still watching your luggage slowly crawl out on the belt.

Did your luggage disappear when the plane took off?  Of course not.  The luggage was already on the way when it took off.  Likewise, the gravity (and the CMBR) that was on its way when parts of the universe became causally disconnected is still on its way.  The causal disconnect does not stop it.

What I said was that these lagrangian fields/waves are generated by gravitational fields/waves, and they are, are they not?

No, they are not.  There are no "Lagrangian fields" that keep things in those locations.  Lagrange/libration points are the RESULT of gravitational fields and the laws of motion.  Fields are not the same as waves, as Exchemist explained.

Given they're produced by the gravity of large bodies like those of the sun & earth, or the sun & the moon, as the link text says, which are all moving through space orbiting the sun or the sun circling the Milky Way & therefore are generating gravitational waves

Yes.  Oscillating masses cause gravitational waves.

to form the gravity fields of Lagrange points-which themselves do not stay set, they orbit the sun and will release gravity waves just like everything else.

Incorrect.  From the perspective of an object in the Lagrange point, both bodies (in our case the Sun and the Earth) are static sources.  They do not move with respect to the Lagrange point.  That means the fields are static, not dynamic (or to use your terms, fixed, not "waves.")

No u

Well, there you go.

Edited by billvon
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What I said was that these lagrangian fields are generated by gravitational waves, and they are, are they not?

Given they're produced by the gravity of large bodies like those of sun or the moon, which are moving through space & therefore are generating gravitational waves to form the gravity fields of Lagrange points.

You said two things, both of them incorrect.

First you said that "by very definition a gravitational field is an effect of a gravitational wave". This is quite wrong, as I have just explained.

Then you said that Lagrangian points are the effect of gravitational waves.  This is also wrong. Lagrangian points are the result of combined static (or nearly static) gravitational fields, resulting in local maximum or minimum points in the net resultant potential of gravitational and centrifugal force, when seen from the viewpoint of a rotating frame of reference: Contour diagram illustrating this here: https://en.wikipedia.org/wiki/Lagrangian_point#/media/File:Lagrange_points2.svg

These maximum and minimum points are calculated without any reference at all to the idea of gravitational waves, as you can easily verify if you look up Lagrangian points in the Wiki article from which that diagram is taken: https://en.wikipedia.org/wiki/Lagrangian_point

There is a quite easy to read Wiki article about gravitational waves, here: https://en.wikipedia.org/wiki/Gravitational_wave

But these things play no practical role in most celestial mechanics. Though it is interesting to note in this article, under "Detection", that 30yr observation of the orbital period of a binary star system has in fact resulted in a change in period consistent with the radiation of gravitational wave energy (cf. my comments in my previous post about energy being radiated by these waves and this energy having to come from somewhere.)  :)

Edited by exchemist
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The gravity of the matter that made up the Earth IS ALREADY THERE. Just as the light from the very early universe (the CMBR) IS ALREADY HERE.

Okay, the CMBR is from when the universe was, what, 137,000 years old?

The universe was tiny, everything was causally connected, however, unless you're with the cold bang theory, space has expanded so much since then that light and gravity no longer had the time to make it here from beyond the particle horizon. Back then, there was no particle horizon, everything was closer together.

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You said two things, both of them incorrect.

First you said that "by very definition a gravitational field is an effect of a gravitational wave". This is quite wrong, as I have just explained.

Then you said that Lagrangian points are the effect of gravitational waves. This is also wrong. Lagrangian points are the result of combined static (or nearly static) gravitational fields, resulting in local maximum or minimum points in the net resultant potential of gravitational and centrifugal force, when seen from the viewpoint of a rotating frame of reference: Contour diagram illustrating this here: https://en.wikipedia.org/wiki/Lagrangian_point#/media/File:Lagrange_points2.svg

These maximum and minimum points are calculated without any reference at all to the idea of gravitational waves, as you can easily verify if you look up Lagrangian points in the Wiki article from which that diagram is taken: https://en.wikipedia.org/wiki/Lagrangian_point

Any gravitational field produces a gravitational wave no mass in the universe sits still.
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Any gravitational field produces a gravitational wave no mass in the universe sits still.

That is totally wrong.

Read the Wiki article: it explains exactly the conditions needed to produce gravitational waves. You need acceleration and resulting motion which is not spherically symmetrical.  A body on its own in space does not produce them.

And, I repeat, Lagrangian points have nothing to do with gravitational waves.

Just do the reading and it will all become clear.

Edited by exchemist
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That is totally wrong.

Read the Wiki article: it explains exactly the conditions needed to produce gravitational waves. You need acceleration and resulting motion which is not spherically symmetrical.

Just like the interaction of the gravity of the earth & the sun on a satellite at the right distance from both bodies, it wouldn't be in the center because the sun has strong gravity, it would be right at L1. Hence, equilibrium. Pinning the satellite down, so that it doesn't fall into either the sun or the earth.

Edited by Super Polymath
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That is totally wrong.

Gravitational waves are postulated to occur when there is a movement of mass, creating a sudden alteration in the strength of the gravitational field at some point in space. It is postulated that this change in gravitational field should travel outwards from the source of the disturbance at the speed of light, constituting a "gravitational wave".

&, again, it's not postulated, it's tested.

Edited by Super Polymath
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Just like the interaction of the gravity of the earth & the sun on a satellite at the right distance from both bodies, it wouldn't be in the center because the sun has strong gravity, it would be right at L1. Hence, equilibrium. Pinning the satellite down, so that it doesn't fall into either the sun or the earth.

Which has nothing to do with gravitational waves. Right? Do we agree on this now?

&, again, it's not postulated, it's tested.

Don't be silly. Read the Wiki articles I have referenced.

I repeat, yet again, that (1) gravitational waves are irrelevant to most celestial mechanics, including Lagrange points, and (2) gravitational waves require motion of the masses, of a particular kind, involving acceleration (just like radiation from a dipole antenna) and motion that is not spherically symmetrical.

Edited by exchemist
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Which has nothing to do with gravitational waves. Right? Do we agree on this now?

Don't be silly. Read the Wiki articles I have referenced.

I repeat, yet again, that (1) gravitational waves are irrelevant to most celestial mechanics, including Lagrange points, and (2) gravitational waves require motion of the masses, of a particular kind, involving acceleration (just like radiation from a dipole antenna) and motion that is not spherically symmetrical.

if we weren't in fact referring to gravity itself as a wave than the test involving Jupiter and the quasar I cited would have been meaningless. And that's a logical conclusion.

As a quasar and Jupiter don't have some special acceleration to account for the production of gravity waves

Edited by Super Polymath
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If you can see a distant point of light then the contribution of gravity from that source has reached you. Knowing that your eye detected only a miniscule portion of the total radiation from that source, space is full of radiation and gravitational effects. Being immersed in this volume, the net gravitational effect fluctuates minutely around zero. I.e. it’s not significant.

refer to drawing below:

Given two identical objects of 1 unit of mass each, located opposite each other on a 2 unit diameter circle.

The question is: with the pair in the x or y direction, where would a mass of 2 units be located to produce the same gravitational effect on the test object at s?

The tick marks x and y (.54 and -.24 units off center), show these locations. demonstrating that the gravitational effect depends on the distribution of matter. In general, the center of attraction will not coincide with the center of mass. The sphere is one exception.

gravitational waves,

require special conditions.

With objects aligned along x, as they rotate clockwise, the effective center of mass oscillates between x and y in a highly elliptical path (not shown) at 2x the orbital frequency. S could detect variations in gravitational effects with a highly sensitive instrument. At astronomical disances, the masses would have to be huge.

Note, this is derived using newtonian physics.

https://app.box.com/s/54m3ncl7by73rfdf83r94g4gaf7eqhly

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Because gravity waves & their speed also involve first point on causal limits

All of which confirmed by admin Sanctus in post liked by admin buffy

Edited by Super Polymath
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Gravitation is just the same. A body with mass is surrounded by a static gravitational field. No radiation, no energy transmission, no waves. (Thinking about energy makes this obvious: if a wave were being propagated it would carry away energy, so the mass would lose energy over time. Where would this energy come from - what energy source in the body would be thereby depleted? It makes no sense.) If you want to think of it in terms of relativity, the curvature of spacetime is not changing: it has a fixed shape. No waves.

Very true and an important point. The static gravitational field of a single mass does not have any energy and therefore cannot do any work. The static field does not drain any energy from the mass that produced it.

This is apparent from dimensional analysis. Energy = force x distance and has the dimensions of ML2T-2 while a gravitational field only has the dimensions of L2T-2. Obviously, a gravitational field contains no energy until another mass is introduced.

If the second mass is stationary, there will be gravitational potential energy. If the second mass is moving, then some of the gravitational potential energy is transformed into kinetic energy. When the second mass is orbiting the first, it is constantly falling inward so gravitational potential energy is exchanged for the orbital kinetic energy exactly; energy is conserved and the mass can orbit indefinitely.

As long as the orbital distance remains constant, there is no energy released from the system and thus no gravitational waves propagate outwards.

Gravitational waves are postulated to occur when there is a movement of mass, creating a sudden alteration in the strength of the gravitational field at some point in space. It is postulated that this change in gravitational field should travel outwards from the source of the disturbance at the speed of light, constituting a "gravitational wave".

Yes. For example, when neutron stars orbit one another the gravity is so great that they are pulled together and as they get closer they accelerate toward each other at great speed, releasing a great deal of gravitational energy in the form of gravitational waves, travelling at the speed of light. This has already been detected.

On Lagrange Points: While Lagrange points do exist, they have been calculated only as a solution to a two-body problem, such as earth-moon or earth-sun. Calculating a three-body solution, such as earth-moon-sun gets very difficult (I think impossible in closed form). When you add in even more bodies, it is certainly impossible. The presence of Lagrange points does not establish that there are points in space with zero gravity; only that there are points where the gravitational forces from two bodies effectively cancel out.

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The presence of Lagrange points does not establish that there are points in space with zero gravity; only that there are points where the gravitational forces from two bodies effectively cancel out.]

Why does this sound exactly like what I said on the first or second page about gravitational neutralization.

Wait, who brought up Lagrange points?

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if we weren't in fact referring to gravity itself as a wave than the test involving Jupiter and the quasar I cited would have been meaningless. And that's a logical conclusion.

As a quasar and Jupiter don't have some special acceleration to account for the production of gravity waves

This is wrong too. For the umpteenth time, gravity itself is not, repeat not, a wave. If you read the various Wiki articles I have drawn to your attention you should be able to see that.

Two astronomical bodies in orbit around their common centre of mass constitute an accelerating non-spherically symmetric system and as such can be expected, according to my previous posts, billvon's posts and the Wiki article, to produce a (tiny) amount of gravitational radiation, in addition to exerting their normal static gravitational field.

That does not, repeat not, mean that "gravity itself is a wave". Obviously.

P.S. OceanBreeze's contribution is fully consistent with what we have all been saying. It does not matter who brought up Lagrange points. What matters is that the statements you about them that show a misunderstanding of the relevant physics, which we are trying in our various ways to rectify.

I really do ask you to reflect on what we have all said and read the articles at least, before running the risk of posting more wrong physics.

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This is wrong too. For the umpteenth time, gravity itself is not, repeat not, a wave. If you read the various Wiki articles I have drawn to your attention you should be able to see that.

Two astronomical bodies in orbit around their common centre of mass constitute an accelerating non-spherically symmetric system and as such can be expected, according to my previous posts, billvon's posts and the Wiki article, to produce a (tiny) amount of gravitational radiation, in addition to exerting their normal static gravitational field.

That does not, repeat not, mean that "gravity itself is a wave". Obviously.

P.S. OceanBreeze's contribution is fully consistent with what we have all been saying. It does not matter who brought up Lagrange points. What matters is that the statements you about them that show a misunderstanding of the relevant physics, which we are trying in our various ways to rectify.

I really do ask you to reflect on what we have all said and read the articles at least, before running the risk of posting more wrong physics.

None of this relevant, Billvon couldn't even comprehend causal limits, and I was originally correct about how the gravitational waves of the sun & earth and moon & earth literally neutralize each other out when acting on a third body, like a satellite. The rest of it, your whole argument, is a hack at unnecessary addendums.

"But satellites or space dust in Lagrange points don't produce gravity waves! They produce fields! Shapes!"

Is basically what your argument has been reduced to. An argument on purely discrediting the person who demonstrated that microgravity has a limited reach & can be neutralized. That ticked everyone off for whatever reason.

Edited by Super Polymath

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