[VernonNemitz]

Vernon when you say, "Prove it." that is somewhat like a bible thumper telling me I can't prove God doesn't exist therefore that is proof God does exist. The onus should be on the bible thumper to provide the proof of Gods existance.

  And my last messages to Farsight indicate we have rather more evidence for the actuality of virtual particles than their absence.  It's not my problem if he can't accept the facts.  (With respect to my other challenge, why, there's an overview of one logical QM version of gravitation right here: http://knol.google.com/k/vernon-nemitz/simple-quantum-gravitation/131braj0vi27a/2 )

Perhaps you'd be interested in a purely philosophical Question, "Why is there Something rather than Nothing?" --which could apply to anything, God included, if one chooses to believe that God exists.

My answer to that Question is derived from a counter-Question, "If Nothingness was the only State, then what would there be to prevent Something from existing?"  Obviously the answer to this question is "Nothing", and therefore it would be paradoxical if Something did not exist.  Well, the virtual particles in the vacuum (also known as vacuum fluctuations or the vacuum self-energy) are an extremely close match to this philosophical view; they represent Something and Nothing near-simultaneously existing everywhere and all the time.  And some physicists consider the entire Universe to be just a giant temporary fluctuation in Nothing....

[lightarrow]

Of course they will accelerate even in the absence of any gradient, provided there is a gravitational field...

If a gravitational field is there, there's a gradient there, lightarrow. There has to be some form of gradient, otherwise things wouldn't fall down.

A gradient of potential, not of the field. Vernon was talking about a gravitational *field*. Maybe it could seem nitpicking for you, but it's always better to be, because people could confound itself (and this already happened on this forum sometimes ago exactly on this very subject).

[VernonNemitz]

Of course they will accelerate even in the absence of any gradient, provided there is a gravitational field...

If a gravitational field is there, there's a gradient there, lightarrow. There has to be some form of gradient, otherwise things wouldn't fall down.

A gradient of potential, not of the field. Vernon was talking about a gravitational *field*. Maybe it could seem nitpicking for you, but it's always better to be, because people could confound itself (and this already happened on this forum sometimes ago exactly on this very subject).

I'm pretty sure you will find that a field practically always includes a gradient --especially if it can be computed as if arising from a point-source (such as gravity from an object's center of mass).

[lightarrow]

I'm pretty sure you will find that a field practically always includes a gradient --especially if it can be computed as if arising from a point-source (such as gravity from an object's center of mass).

"Especially" in this case is a bit eufemistic  [].
Of course I was talking about a region of space small enough and distant enough from point-like sources so that the field could be considered as uniform (and don't tell me that, however, a mathematically totally uniform field is impossible, we are talking about physics; furthermore, an inertial field is equivalent to a gravitational one).

[lyner]

The reason that things 'fall down' is a gradient in potential , not a field gradient. It isn't hard to produce a region of uniform gravitational field even on Earth - things will still fall down in it.

[VernonNemitz]

Talk about nitpicking.  It seems to me that the practically-always-existing gradient of a field is equivalent to a gradient of potential.  If an external gravitational field wasn't present, affecting some particle, there would be no gravitational potential energy associated with the particle, in that field, and thus no potential to fall.  Two aspects of one thing.  Like gravitational mass and inertial mass are postulated to be two aspects of one thing.  Like salt is a necessary nutrient in small quantities, and deadly in large quantities; two aspects of the same thing.

[lightarrow]

Talk about nitpicking.  It seems to me that the practically-always-existing gradient of a field is equivalent to a gradient of potential.  If an external gravitational field wasn't present, affecting some particle, there would be no gravitational potential energy associated with the particle, in that field, and thus no potential to fall.  Two aspects of one thing.  Like gravitational mass and inertial mass are postulated to be two aspects of one thing.  Like salt is a necessary nutrient in small quantities, and deadly in large quantities; two aspects of the same thing.

Then, space and velocity (for example) are the same thing? They "only" differ because one is the derivative of the other...

[VernonNemitz]

Then, space and velocity (for example) are the same thing? They "only" differ because one is the derivative of the other...

That particular derivation requires including an additional thing, time.  Why aren't both a field gradient and a gradient-of-potential as static as Space?  A typical recreation-park slide (for children) has a gradient and by itself is typically considered to be quite static.  I suppose I'm missing something....

[Farsight]

PROVE IT. Because the definition of "virtual" that I use is "temporary". Their existence, By Definition, is a violation of Energy Conservation --an allowed temporary violation.

There's energy in an electron's electric field. It doesn't vary, it doesn't violate conservation of energy, and it isn't temporary. The mathematics of the attraction between the electron and the proton can be modelled using virtual particles, but saying that these are real but temporary particles popping in and out of existence is taking QED too far. It's not what Feynman intended. He intended them as accounting units. Read http://www.amazon.co.uk/QED-Strange-Theory-Penguin-Science/dp/0140125051 to check this out.  

If you think "virtual" means something else, that's your problem, not mine.  I know exactly what I'm talking about in this context; temporary existence can be Very Real. And that's why the Casimir Effect is a very real side-effect.

Virtual means virtual. As in not real.

I don't need to think of that, when virtual particles are much better at explaining things.

But they aren't better at explaining things. When you fire a plate up into the sky at 12 km/s you give the plate some energy. You don't give it to the earth, or the earth's gravitational field, you give it to the plate, and that plate achieves escape velocity and leaves the system. When you reverse this scenario, you have to accede that that the energy of a falling plate comes from the plate. The idea that it comes from the earth via virtual gravitons travelling at superluminal velocities is not supported by any scientific evidence.

Look up the history of the pi-meson (pion).  Predicted to have certain properties, to exist as temporary particles to explain why protons stay together in an atomic nucleus, the "real" form of that particle was later found to possess the specified properties.  What overcomes the electrostatic repulsion of protons if not virtual pions? (Certainly not virtual gluons; those are locked inside protons and charged pions, holding those particles' constituent quarks together.

Pions have a lifetime of 8.4 x 10^-17 seconds and consist of two quarks. Neutrons hold protons tegother, and I rather think we're getting off topic with this.

Oh, I forgot, since separated quarks have never been seen, you probably "dis" them as being merely hypothetical. Nevertheless, they actually have been detected as individual particles (while not especially separated): http://en.wikipedia.org/wiki/Parton_(particle_physics)

They're partons. Parts. Even Gell-Mann considered them to be subunits, see http://www.achievement.org/autodoc/page/gel0int-1. You want to get a handle on this? Look at the picture of the trefoil knot below:



Now start from the bottom left and follow round looking at crossing points. Ignore crossings-under. Only look at crossings-over. Now call out each crossing direction in terms of whether it's up or down.  

Your evanescent wave hasn't got a chance, to explain complex stable nuclei, and therefore is a wrong explanation. Worthless. So if you want to claim virtual particles aren't real enough, then you need a better alternative, also able to explain the existence of atoms more complex than hydrogen.

It isn't "my" evanesent wave. The evanescent wave is also known as the near-field in radio transmitters. Check out http://en.wikipedia.org/wiki/Near_and_far_field and search on evanescent:

Rather, in the near field, it is sometimes useful to express the contributions as a sum of radiating fields combined with evanescent fields, where the latter are exponentially decaying with r. And in the source itself, or as soon as one enters a region of inhomogeneous materials, the multipole expansion is no longer valid and the full solution of Maxwell's equations is generally required.

In quantum mechanical terms, the far-field is due simply to radiation of classical photons. These remove energy from the transmitter whether they are immediately absorbed or not. By comparison, the near-field, if it must be seen in quantum terms, may be thought of being composed of virtual photons, which have a more evanescent existence.

You are essentially saying it will be forever impossible to devise a quantum theory of gravitation.

Yes, that's right. Gravity doesn't work like that.  

Your bald claims are totally worthless without supporting evidence.  You don't even have logical self-consistency on your side, as was pointed out to me years ago in that UseNet discussion, while I do now have logical self-consistency on my side (and possibly a tiny amount of evidence;

Mine aren't the bald claims. There is no evidence for virtual gravitons. And I do have logical consistency on my side. The energy of the falling plate comes from the plate.  

Have you read that "Simple Quantum Gravitation" knol yet?  Here's a related teaser: http://adsabs.harvard.edu/abs/2004AIPC..699.1138M ).

No, I haven't read it yet. Sorry. If you spent less time throwing up hypotheticals to avoid the simple logic of the falling plate, I'd have more time to do so. I had a quick look at that teaser and didn't like what I saw re the existence of mass fluctuations and their use in exotic propulsion schemes.

Gravitons are not yet detectable. Unless you have proof they cannot exist, you would be foolish to say they will never ever be detectable...

No Vernon, it's foolish to carry on year after year adhering to a hypothesis that has no supporting evidence.

..And your inability to accept the Real Fact of "spooky action at a distance" is not a valid reason!!!

It isn't a real fact. We have no evidence of virtual gravitons rattling around at superluminal velocities. A plate falls because there's a gradient in its local space. It's observable, via the Pound-Rebka experiment and GPS.

Now please, let's try to keep on topic and keep the posts briefer.

Ron: well said.

[Farsight]

All: take a fairly small region of space, such as a room, and there's no measurable gradient in the gravitational field strength in that room. Drop an object from the top of the room or the middle of the room, and you measure the same acceleration of 9.8 m/s. But the object falls down, so there is some kind of gradient in that room. Sophie called it a gradient in gravitational potential, but we can take a step further. Check out the Pound-Rebka experiment, which is extremely sensitive: http://en.wikipedia.org/wiki/Pound%E2%80%93Rebka_experiment. There's a detectable frequency shift. As a photon travels downwards, its observed frequency changes. Some ascribe this to virtual gravitons travelling instantly up from the ground, but it's far simpler to think of this as a change in the local properties of the space that the photon travels through. This is totally in line with Einstein, who said in 1920:

Mach’s idea finds its full development in the ether of the general theory of relativity. According to this theory the metrical qualities of the continuum of space-time differ in the environment of different points of space-time, and are partly conditioned by the matter existing outside of the territory under consideration.

This space-time variability of the reciprocal relations of the standards of space and time, or, perhaps, the recognition of the fact that “empty space” in its physical relation is neither homogeneous nor isotropic, compelling us to describe its state by ten functions (the gravitation potentials gμν), has, I think, finally disposed of the view that space is physically empty.

This gradient in the gravitational potential can be considered to be a "pressure" gradient or a "density" gradient, but I don't like either word when talking about space. The best I can offer is a gradient in the energy density of space, or a gradient in vacuum energy. It's observable as a gradient in gravitational time dilation. Think about c. You will always measure c to be 299,792,458 m/s. But gravitational time dilation is only radial. So if you're measuring c using a horizontal apparatus, the metres don't change. But the seconds are different because of the time dilation, so the c is different too. And if c is different, that means Z0 is different. That gradient is a gradient in vacuum impedance. But you can't measure it locally, because of what pair production is telling us: electrons are quite literally made of light. This applies to other things too, like protons, and you, and your rods and clocks.

It's like you've got a mechanical clock and you plunge it into an oil bath. It now runs slower, because of the viscosity, because the environment has changed. But you can't see it, because you're like a clockwork man, and you've jumped in after it. 

[PhysBang]

You want to get a handle on this? Look at the picture of the trefoil knot below:

Now start from the bottom left and follow round looking at crossing points. Ignore crossings-under. Only look at crossings-over. Now call out each crossing direction in terms of whether it's up or down.  

This is embarrassing! Your justification for ignoring the mountains of evidence in favour of the standard model of particle physics is a picture of a knot? Can you explain what this knot has to do with any experiment ever performed? Can your knot produce the formulae of quantum mechanics?

Mine aren't the bald claims. There is no evidence for virtual gravitons. And I do have logical consistency on my side. The energy of the falling plate comes from the plate.  

Virtual gravitons aren't the question here. You have made claims that the quantization of gravity is impossible. Where is the evidence?

If you spent less time throwing up hypotheticals to avoid the simple logic of the falling plate, I'd have more time to do so. I had a quick look at that teaser and didn't like what I saw re the existence of mass fluctuations and their use in exotic propulsion schemes.

The problem is, VN is at least attempting to address actual science that explains actual observation. Your theory of gravity cannot actually predict how fast a plate will fall. This is a serious, serious problem with your theory, as we can have no reason to believe in your theory and no basis to use your theory to reject anything.

[Ron Hughes]

As vernon says, " Gravity and inertia are two aspects of the same thing. " Time dilation.

[PhysBang]

Mach’s idea finds its full development in the ether of the general theory of relativity. According to this theory the metrical qualities of the continuum of space-time differ in the environment of different points of space-time, and are partly conditioned by the matter existing outside of the territory under consideration.

This space-time variability of the reciprocal relations of the standards of space and time, or, perhaps, the recognition of the fact that “empty space” in its physical relation is neither homogeneous nor isotropic, compelling us to describe its state by ten functions (the gravitation potentials gμν), has, I think, finally disposed of the view that space is physically empty.

This gradient in the gravitational potential can be considered to be a "pressure" gradient or a "density" gradient, but I don't like either word when talking about space. The best I can offer is a gradient in the energy density of space, or a gradient in vacuum energy. It's observable as a gradient in gravitational time dilation. Think about c. You will always measure c to be 299,792,458 m/s. But gravitational time dilation is only radial. So if you're measuring c using a horizontal apparatus, the metres don't change.

Let's stop there. Because what does Einstein say about those ten functions in the quotation above? He says that they determine the metric of spacetime. That means that the metres do change. You can't simply cherry-pick Einstein and prove whatever you want. If you want to invoke the 1920 work by Einstein, then you have to accept the mathematical theory that Einstein uses, the mathematical theory that you seemingly cannot understand and constantly contradict.

[lyner]

VernonNemitz

Talk about nitpicking.  It seems to me that the practically-always-existing gradient of a field is equivalent to a gradient of potential.

I'm not nitpicking - I'm talking about definitions. If you can't stick to them, what chance have you got?
If you don't understand the terms then you shouldn't be using them to prove points.

[Farsight]

Stop carping, PhysBang, and get up to speed: http://arxiv.org/find/grp_physics/1/ti:+AND+quantum+knot/0/1/0/all/0/1. There is no evidence to support the quantization of gravity, and the evidence against it is simple: energy causes gravity, a photon conveys energy, and it doesn't approach you in steps. The resultant gravity rises smoothly. And this isn't my theory of gravity, it's Albert Einstein's. He talked about the variable speed of light and the equations of motion, not curved spacetime. Plus others have looked into it way before me, see http://arxiv.org/abs/0708.3518 and http://www.ag-physics.de/. And please, go and look up length contraction in the Schwarschild metric. It's radial. The metric changes, but not the transverse metre. By the way, as you said to everybody earlier, my name is John Duffield, are you Albert C Marshall formerly of Sandia?

[PhysBang]

Stop carping, PhysBang,

Pointing out that you consistently use cherry-picking of quotations in order to deceptively make your case is not carping. You malign the work of Einstein in order to inflate your own appearence, pure and simple.

and get up to speed: http://arxiv.org/find/grp_physics/1/ti:+AND+quantum+knot/0/1/0/all/0/1.

There is absolutely nothing in those papers that relates to your use of knots other than the five letters in the word "knots". Show the math.

There is no evidence to support the quantization of gravity, and the evidence against it is simple: energy causes gravity, a photon conveys energy, and it doesn't approach you in steps. The resultant gravity rises smoothly. And this isn't my theory of gravity, it's Albert Einstein's. He talked about the variable speed of light and the equations of motion, not curved spacetime.

"Curved spacetime" is the basis for Einstein's theory. It is the words that we use to refer to Einstein's use of Riemannian geometry. That you cannot understand this is not surprising, as you make no effort to actually learn Einstein's work.

And nobody is claiming that spacetime isn't continuous in General Relativity. Rather, they are claiming that we have to develop a new theory. Some types of successor theories are on the verge of being rejected by the evidence, others are not. So far, there is no evidence that strongly supports any successor theory.

Plus others have looked into it way before me, see http://arxiv.org/abs/0708.3518 and http://www.ag-physics.de/.

That you are not alone in doing bad physics is not much of a defence.

And please, go and look up length contraction in the Schwarschild metric. It's radial. The metric changes, but not the transverse metre.

OK, show us the math.

By the way, as you said to everybody earlier, my name is John Duffield, are you Albert C Marshall formerly of Sandia?

Is your name a secret? You are trying to sell your book here, aren't you?

[Farsight]

You are carping, PhysBang, that's all you ever do. And I certainly don't malign Einstein whatsoever. Curved spacetime is not the basis for Einstein's theory, as we see when we actually read The Foundation of the General theory of Relativity, and as Pmb showed in the arXiv paper that you dismissed as crank, just as you dismiss anything unfamiliar, like you'll dismiss these trefoil HEP papers: http://arxiv.org/find/grp_physics/1/ti:+trefoil/0/1/0/all/0/1. And no, I'm not selling anything, I'm trying to discuss physics. On a discussion forum. If you don't want to, that's up to you, but stop trying to spoil the forum for everybody else. And I repeat: are you Albert C Marshall formerly of of Sandia?

[AllenG]

Gentlemen,  argue the physics and please leave the personal snipes out of the conversation.

[Farsight]

OK, let's get back to the original post and work it through:

So matter can basically be thought of as just potential energy because matter can be turned into energy and theoretically vice-versa, does that mean when I lift up a plate and increase it's potential energy, i've technically increased its mass?

Let's imagine we're on an earth-sized planet with no atmosphere, and that the plate is robust and isn't going to shatter. We use something like a long-barrelled cannon to fire it upwards with a velocity of 10km/s. Lightarrow thought this:

The mass is increased, but not the mass of the plate: the mass of the system Earth-plate.

However there's a problem here with conservation of energy. We used chemical energy in the propellant, and converted it into the plate's kinetic energy. We haven't added any energy to the Earth-plate system, and if we had, the gravity of that system would increase. The earth doesn't recoil in any measurable fashion, so the distribution of 1/2 mv² kinetic energy is not symmetrical. That kinetic energy is definitely in the plate: 10km/s is very measurable.

As the plate rises it slows down, and we say the kinetic energy is being converted into potential energy. But because it started with 10km/s the plate doesn't have escape velocity. Hence there will come a point when all of the kinetic energy is converted into potential energy, and the plate stops momentarily.

At this point the Earth and the plate are at rest with respect to one another, just as they were before we fired the plate up into the sky. All of that 10km/s has been converted into potential energy, and the plate has more energy, and so more mass than previously. It isn't obvious where it's gone, but if you look at electron spin within the plate and then gravitational time dilation, all the electrons are spinning at a greater rate than they were. You can't measure anything locally because it's an immersive scale-change that also affects your measuring devices. You can only detect this via say the GPS clock adjustment.

People attempt to evade the fact that the potential energy is in the plate, and say it's in the gravitational field or the earth rather than the plate, but take a look at what happens when you fire the plate at 12km/s. Here the plate does have escape velocity, and it leaves the system, taking way all the original mass/energy of the plate along with all the kinetic energy we gave it. The mass/energy of the earth is diminished, and the gravity is so reduced. It's cut and dried: that potential energy went into the plate.

[VernonNemitz]

There's energy in an electron's electric field. It doesn't vary, it doesn't violate conservation of energy, and it isn't temporary.

That's an ordinary electron, possibly.  Certainly "conventionally".  I won't argue that point at this time, because it is NOT a virtual electron, and therefore irrelevant to the present discussion.

The mathematics of the attraction between the electron and the proton can be modelled using virtual particles, but saying that these are real but temporary particles popping in and out of existence is taking QED too far. It's not what Feynman intended. He intended them as accounting units.

So?  Who says Feynmann Is The Last Word on this subject?  Feynman proposed that anti-particles move backward through time, too, as a bookkeeping notion.  And a lot of physicists talk about "negative binding energy", another bookkeeping notion (I don't know who originated it), as if it was quite real.  If you are going to say that negative binding energy cannot be real simply because it is an accounting trick, what are you going to put in its place?  Your potential-energy-as-mass-of-plate notion does NOT fit the math that describes the behavior of nuclear particles in the Strong-Force field-gradient.  I see you have neglected to offer any other reason why the virtual-accounting trick can't be real, besides, duh, "Feynmann said so."  Whoop-te-do.  How does he know???  Not to mention, he died more than 20 years ago, and thus missed a lot of recent theoretical developments.  Maybe he would be now be saying some of the same things I've been saying to you.

Virtual means virtual. As in not real.

Wrong again.  Educate yourself: http://dictionary.reference.com/browse/virtual  --a thing can be called "virtual" if it has some of the virtues of something else.  But obviously it has to exist in some fashion to have any virtues at all!!!  The reality of that existence is all I need.  Also for your edification: http://en.wikipedia.org/wiki/Virtual_particle

But they [virtual particles] aren't better at explaining things. When you fire a plate up into the sky at 12 km/s you give the plate some energy. You don't give it to the earth, or the earth's gravitational field, you give it to the plate, and that plate achieves escape velocity and leaves the system.

Incomplete. It's initial velocity is reduced by about 11 km/s, before it escapes.  The kinetic energy associated with that velocity has become potential energy.  We are agreed that it takes the form of mass.  Well, if the Earth's gravity field sucked that KE out of the plate, during the escape, why shouldn't the Earth end up with most of that potential-energy-stored-as-mass?

When you reverse this scenario, you have to accede that that the energy of a falling plate comes from the plate.

I most certainly do not.  In QM terms we would be talking about an attractive force; the Earth pulls the plate toward it, more than the plate pulls the Earth.  How many times after you pulled on something, accelerating it, were you able to say that the pulled object was the source of the kinetic energy it acquired?

The idea that it comes from the earth via virtual gravitons travelling at superluminal velocities is not supported by any scientific evidence.

DO NOT TWIST WHAT I HAVE WRITTEN. Virtual gravitons don't have to be superluminal; they merely need to be "entangled" with their mass-of-origin.  If one is absorbed by some other mass, then it is the entanglement that allows the absorbing mass to acquire kinetic energy at the expense of the origin-mass.  The quantity transferred is equal to the energy of the virtual graviton at that point in its lifespan (its Uncertain energy diminishes at a rate ideally describable by the curve of the function 1/x).  It is Observed Fact that entanglement-events, when they are triggered, act instantaneously; it is the essence of "spooky action at a distance".  And yet the whole thing can make better sense if a virtual graviton is perceived as being "semi-real"; if it is absorbed, then the absorbing mass acquires its energy.  Simple.  And if it is never absorbed, the origin-mass loses nothing; that's the other side of the "semi-real" coin.

Neutrons hold protons together.

HOW???  --and no, we are not off-topic at all, since virtual pions can provide a detailed explanation for how protons can stay together in an atomic nucleus (thanks to present knowledge about quarks, heh!).  And, while neutrons are involved, the key point here is that virtual particles offer the best explanation.  If you want to say virtual particle don't exist, then you need to say much much more than merely, "Neutrons hold protons together."

They're partons. Parts.

They were observed parts, in electron-scattering experiments. That was my point. We can say that quarks are real parts of protons because we have observed real parts of protons.  Regarding that knot-picture, I distinctly see, per your "Only look at crossings-over" instruction, a left/right crossing-over.  Another worthless argument on your part, therefore, since it was supposely about up/down crossings only.

It isn't "my" evanesent wave. The evanescent wave is also known as the near-field in radio transmitters. Check out http://en.wikipedia.org/wiki/Near_and_far_field and search on evanescent:

I might need to partly take back some of what I wrote in my last message to you, since it sounds to me, from the description you quoted, that "evanescent" is synonymous with "virtual". (And since QM has the wave-particle duality, "evanescent wave" translates as "virtual particle" quite easily!)

You are essentially saying it will be forever impossible to devise a quantum theory of gravitation.

Yes, that's right. Gravity doesn't work like that.

Just because you say so, that doesn't mean it's true.  Evidence, please?

Mine aren't the bald claims.

Of course they are.  See previous quote.

There is no evidence for virtual gravitons.

Duh, it is premature to require such evidence, simply because there isn't an accepted Theory yet, that involves virtual gravitons.  YET, I said.  After there exists such a Theory, then will be the time to see what evidence might be gathered in support of it.  On the other hand, gravitation exists, does it not?  Why cannot that count as evidence?

And I do have logical consistency on my side.

HaHaHaHaHaHaHaHaHaHa!!!!!  See above, about pulling on something.

The energy of the falling plate comes from the plate.

Bad Logic As I've pointed out above and elsewhere.

If you spent less time throwing up hypotheticals to avoid the simple logic of the falling plate, I'd have more time to [read your stuff].

I'm a patient fellow. I don't require instant replies to what I write.  And the so-called "logic" of your falling plate is quite "ill".

I had a quick look at that teaser and didn't like what I saw re the existence of mass fluctuations and their use in exotic propulsion schemes.

Why? Because there might be more types of gravity waves out there, than are dreamt of in your philosophy?  Tough!  A propulsion scheme might be a simple as, "If I build a gravity-wave generator such that it emits waves moving in one direction, then Conservation of Momentum requires the machine to move in the other direction."

...it's foolish to carry on year after year adhering to a hypothesis that has no supporting evidence.

Sounds like your own hypothesis, much more so than mine.

A plate falls because there's a gradient in its local space. It's observable, via the Pound-Rebka experiment and GPS.

And a correct QM theory of gravitation will make predictions indistinguishable from GR's predictions. Whoop-te-do.  A gradient for virtual-graviton-intensity is as possible as the way the Inverse Square Law typically affects other large quantities of radiated things, like photons.  Since a mass doesn't truly radiate all its virtual gravitons from its "center of mass" (that's a bookkeeping trick!), a rotating mass will have most virtual gravitons leaving it at an angle, with effects equivalent to the twisted space that GR describes for a rotating mass.  And so on.  The passage of time can be slower in a gravity field if one first considers that "the passage of time" can be described as being associated with a particular rate of some particular interaction.  Well, in a gravity field that particular interaction isn't the only thing going on; the interacting parts are also interacting with lots of virtual gravitons.  If each particle can only do one interaction at a time, then it logically figures that the deeper in a gravity well, the more time a particle spends interacting gravitationally instead of with anything else; the rate of interaction with anything else has diminished, exactly as if time was passing more slowly, for those other interactions.  There is no way to tell the difference, between that and the time-slowing of GR.  And so on....