[mad aetherist (OP)]

So what if we go back to Einstein's wordages & every time he mentions his elevator stuff we change the wording to say that it is an elevator with zero width & zero length & zero height (or re his box or whatever in the original).

The box can be any size you like if the field is actually uniform, and if the acceleration is actually continuous.  All the tests you have suggested are just detecting the nonuniformity of the field, which violates the equivalence principle that continuous uniform acceleration and a uniform gravitational field are indistinguishable from inside a box.

No i think that u do not need to worry about some sort of uniform gravity field. What u mean is of course a constant gravity field, eg in an elevator standing still on Earth. The gravity field might or might not be uniform depending on definition, but it is certainly constant (ignoring slow real world changes due to spin & orbit & moon etc).

[mad aetherist (OP)]

Yes i am now happy with a uniform gravity field, & a uniform acceleration inertial field.

Again, an accelerating box is not an inertial one.
Comment: We are talking about two different inertials here.

No. Think it throo. In the inertial case the photon retains its heading at all times.

The accelerating box is not inertial.

No i dont agree. But praps my inertial is different to your inertial.

Inertial means not accelerating.  Use 'accelerating' if you mean the box being compared to the gravitational field.
Comment: Yes i wont use inertial again.

I dont understand. There is only one frame inside the elevator.

The inertial frame of the elevator is constantly changing because of the acceleration.  It is an accelerated reference frame, not an inertial one, so the clocks at either end cannot stay synched.
Comment: Ok i understand.

Yes i agree. Measuring the ticking rate is easy, measuring true time is usually a problem.

That would not be relativity theory.  Measuring true time is easy.  Pick any clock that runs at true time, and compare everything to that clock.  Funny that the etherists cannot do that.  Nobody for instance states the dilation factor of the standard clock that defines GMT.
Comment: Aetherists believe in an absolute time, which is universal. And that ticking depends on the aetherwind. However i am happy to accept the possibility that gravitational potential can affect ticking (ie in addition to aetherwind effect).

[mad aetherist (OP)]

Just as an aside last month i learnt that nearer the central iron core the value of g increases with depth (after decreasing with depth nearer Earth's surface.

I find this hard to believe.  With each new meter of depth, an incredible amount of mass is put above you that was below before. That should decrease g, not increase it. The force has to decrease to zero at the center after all.

Yes, thats what i thort, but iron is double the density of rock.

OK, I'll buy it.  The density change is quite abrupt going from lower mantle (about 5g/cc) to outer core (9,9g/cc).
Found a graph of g vs depth:
https://upload.wikimedia.org/wikipedia/commons/thumb/5/50/EarthGravityPREM.svg/300px-EarthGravityPREM.svg.png
Acceleration is 9.8m/sec² at the surface, quickly rising to 10, and holding that for a long way in, then increasing to 10.7 at a radius of about 3400 km, and dropping off sharply only from there on in to the center.  Interesting stuff.

And as u said, the plumb thread will point as per g at that depth/ht, not as per the change in g.

[mad aetherist (OP)]

Aetherists believe in an absolute time, which is universal. And that ticking depends on the aetherwind. However i am happy to accept the possibility that gravitational potential can affect ticking (ie in addition to aetherwind effect).

Yes, they believe that.  Yet none of them set up a clock that is actually tuned to actual time, a simple task if they could just compute the dilation factor of local clocks.  Somebody has probably attempted it, but I've not seen any dilation factor published, let alone a consistent one.

This is my idea of how the aetheric theory goes. The only clock that has true ticking is a clock experiencing zero aetherwind -- here that clock must be at rest in the absolute frame -- difficult, the aetherwind blowing throo Earth is say 500 kmps south to north say 20 deg off Earth's spin-axis -- but, actually, easy, because, if a clock & observer are at rest with respect to each other then the clock will appear to be ticking at the same rate as an absolute clock (due to ticking dilation)(in accordance with the Heaviside Voigt FitzGerald Lorentz gamma for ticking dilation).
So all clocks at rest in your small lab all appear to be ticking as per their absolute ticking rate, no tuning needed (its automatic).
Now, to say analyse GPS we need to estimate the aetherwind that will be blowing throo the satellite clock & calculate the expected ticking using gamma.
Here the aetherists will in effect use gamma twice (once automatically)(& once by crunching the relative absolute relative velocity of the satellite compared to an observer in the absolute rest frame)(a long winded way of saying that their V is the estimated aetherwind to be felt by the satellite).
Einsteinians will use gamma once only, they apply it to the relative velocity tween observer (& satellite) sitting on the ground & the satellite in orbit.

[mad aetherist (OP)]

The box can be any size you like if the field is actually uniform, and if the acceleration is actually continuous.  All the tests you have suggested are just detecting the nonuniformity of the field, which violates the equivalence principle that continuous uniform acceleration and a uniform gravitational field are indistinguishable from inside a box.

No i think that u do not need to worry about some sort of uniform gravity field. What u mean is of course a constant gravity field, eg in an elevator standing still on Earth.

Don't tell me what I mean.  I mean uniform.  Constant means it doesn't change over time, and I don't mean that.
Uniform means all the plumb lines are parallel, just like they would be in the accelerating elevator.  Hypothetically possible, but not practical.
Strangely, uniform does not mean that force is identical at different heights, just like it isn't in the elevator.
I may have mistakenly said otherwise.

Ok, i think i get it. Interesting notion.
I think that a uniform gravity field like that is impossible. U could posit that u can get one near an infinite plate. But, note, in this case the force of gravity is constant at any location or distance (ie it would not be in accord with your expected requirements).
 
Strangely, according to aether theory the gravity g near an infinite plate is zero. Believe it or knot. What that means is that there is no gravity field, hencely one cant talk of a uniform gravity field near the infinite plate.

Inside the hollow of a hollow Earth the gravity field must be zero, Einsteinians & aetherists will agree here.  But a zero field cant be called a uniform field, surely.

[mad aetherist (OP)]

Strangely, according to aether theory the gravity g near an infinite plate is zero. Believe it or knot. What that means is that there is no gravity field, hencely one cant talk of a uniform gravity field near the infinite plate.

Sounds like a mark against your aether theory.

In aether theory gravity is due to the acceleration of aether into matter -- in effect the acceleration is due to the convergence of  the inflow streamlines.
For Earth the streamlines converge in 2 dimensions, hencely a 1/RR force field. 
For an infinitely long wire the streamlines converge in one dimension, hencely a 1/R force field.
For an infinite plate there is no convergence, hencely a 0/R or 0/RR force field (ie no force field).
Ranzan has a theory that aether is contractile & that the primary convergence of the streamlines due to aether annihilation in matter is bolstered by a secondary annihilation along the streamlines which magnifies the effect. However if the primary convergence doesnt exist then i suppose that the secondary annihilation doesnt happen either. So no help for any gravity at an infinite plate there.

One spin-off is that the gravity field for a flattish spiral galaxy varies per 1/R. Hencely no need for dark matter.  Sounds like a mark for my aether theory.
Let me explain. If u take a thin slice of a thick infinite wire, & remove the rest of the wire, then a test particle in the plane of the slice will not notice that the rest of the wire has been removed, it will still think that the field is a 1/R field. A spiral galaxy acts much the same as this slice of wire.
But when they do their computer simulations they automatically plug in the Newtonian 1/RR for each star. And then they have to invent dark matter to fill their hole.

[mad aetherist (OP)]

In aether theory gravity is due to the acceleration of aether into matter -- in effect the acceleration is due to the convergence of  the inflow streamlines.

That is a completely different aether theory than the one I know (neo-Lorentz ether theory, as is typically pushed by the anti-relativists).  What you describe here is falsified easily.
Comment: Lorentz in the early days knew nothing of the aetherwind (i dont think that he even knew of a possible wind due to Earth's spin or orbit throo some sort of fixed aether, fixed to the Sun or something). Lorentz probly knew little of the aether annihilation-inflow theory (alltho praps he did, there were similar theories going back a long way). I welcome any falsification.

For Earth the streamlines converge in 2 dimensions, hencely a 1/RR force field. 
For an infinitely long wire the streamlines converge in one dimension, hencely a 1/R force field.
For an infinite plate there is no convergence, hencely a 0/R or 0/RR force field (ie no force field).

You (an admitted non-scientist) made that up.  There is no way Ranzan or some other hero said "0/R or 0/RR".
In fact, it should be for all 3: 1/R^d where d is the number of convergence dimensions.
Comment: Thems 0/R & 0/RR are just some sillyness. If there is no force field for an infinite plate then i cant illustrate it with any equation, or, i can, & that equation is GF=0. I cant say 0/0R or 0/0 or anything like that.
The infinite plate line then works out to 1/R⁰ which is constant gravity, not zero gravity. But Newton worked that out, and didn't need aether theory to do it. It all derives from treating the wire and the plane as point masses with the 1/RR rule.
Comment: Yes that is the Newtonian answer. Aether theory shows zero convergence of inflow streamlines, ie GF=0. Hencely u could have 2 parallel infinite plates & the attraction would be zero.

One spin-off is that the gravity field for a flattish spiral galaxy varies per 1/R. Hencely no need for dark matter.  Sounds like a mark for my aether theory.
Let me explain. If u take a thin slice of a thick infinite wire, & remove the rest of the wire, then a test particle in the plane of the slice will not notice that the rest of the wire has been removed, it will still think that the field is a 1/R field.  A spiral galaxy acts much the same as this slice of wire.

A spiral galaxy is not infinite length in one dimension.  It acts nothing like the wire, sliced or otherwise.
Comment:  None of my wordage infers an infinite L in one dimension for a spiral galaxy. I said a thin slice of a thick wire, in which case i am talking about a circular disc, praps i should have said an infinite cylinder (which would have a 1/R gravity just like an infinite wire). But here i admit that my 1/R analogy where my thin slice retains the 1/R gravity even tho the rest of the infinite thick wire-cylinder has been removed is problematical. So i am still thinking re this stuff.

But when they do their computer simulations they automatically plug in the Newtonian 1/RR for each star.
 And then they have to invent dark matter to fill their hole.

Whereas you do no simulation at all, and declare success because it works in your imagination.
Comment: Yesterday i saw a computer analysis for a certain spiral galaxy & the graph showed that the star velocities exactly followed the computer generated line for 1/R, whereas their 1/RR line went down to near their xx axis.
I think we're getting off topic here.  We were discussing the equivalence principle, and this post is all about a theory irrelevant to that. Comment: Yes. There is a "how gravity works in a spiral galaxy"  thread running at present in New Theories. But that is overflowing with sillyness.  This needs its own 1/R thread, or Dark Matter thread.

[Colin2B]

The spherical cavity results in zero weight everywhere, the equivalent to an inertial frame, but still in a gravity well.

Sorry, I should have been more specific, I didn’t mean a cavity centred on the sphere’s centre, but one offset from the centre. Dont’t have time to do the tex (too much spam around at moment). I think @PmbPhy might have it on his website.
It is also possible to envisage an area on earth where the geoid, due to density variation below the surface, becomes flat over a limited area and plumb lines over that area would be parallel.

[mad aetherist (OP)]

You (an admitted non-scientist) made that up.  There is no way Ranzan or some other hero said "0/R or 0/RR".
In fact, it should be for all 3: 1/R^d where d is the number of convergence dimensions.

Thems 0/R & 0/RR are just some sillyness. If there is no force field for an infinite plate then i cant illustrate it with any equation, or, i can, & that equation is GF=0. ...
Aether theory shows zero convergence of inflow streamlines, ie GF=0.

GF=0 is what you are making up.  At what point in adding objects to a flat array of objects does the gravity suddenly switch off? I could generate infinite energy and reactionless thrust if this were true. You say you welcome falsification, but you don't recognize it when you get it.
Comment: The streamlines are all parallel, hencely the aether inflow is not accelerating. Gravity force is not due to aether velocity, it is due to aether acceleration. Zero acceleration = zero gravity.

None of my wordage infers an infinite L in one dimension for a spiral galaxy. I said a thin slice of a thick wire, in which case i am talking about a circular disc,

Ah, you're slicing it that way.  Such an object does not exhibit the 1/R gravity drop off of a rod with significant length.  The pull from the further parts of the rod have been removed.  Integrating over the mass of the flat object would show this.  Integrating over the mass of the long rod/wire would show the 1/R dropoff of force.  Nothing needs to be infinite.
Comment:  I admit that my analogy isnt watertight, i could be wrong. Once the thin slice (disc) begins to be given some thickness the 1/R starts to revert to a 1/RR relationship. I am still thinking re this.

There is a "how gravity works in a spiral galaxy"  thread running at present in New Theories. But that is overflowing with sillyness.

Ah, Thank you!  You label anything that threatens you 'silliness', and I would actually question my posts if you didn't consider them silly.
Comment: Being an aetherist it is unlikely that i would fully agree with anything in that thread. But when i said sillyness i meant that there appeared to be a lot of microscopic analysis of trivial stuff.

[mad aetherist (OP)]

Albert Einstein (1879–1955).  Relativity: The Special and General Theory.  1920.
XX.  The Equality of Inertial and Gravitational Mass as an Argument for the General Postulate of Relativity
     We imagine a large portion of empty space, so far removed from stars and other appreciable masses that we have before us approximately the conditions required by the fundamental law of Galilei. It is then possible to choose a Galileian reference-body for this part of space (world), relative to which points at rest remain at rest and points in motion continue permanently in uniform rectilinear motion. As reference-body let us imagine a spacious chest resembling a room with an observer inside who is equipped with apparatus. Gravitation naturally does not exist for this observer. He must fasten himself with strings to the floor, otherwise the slightest impact against the floor will cause him to rise slowly towards the ceiling of the room.      1
     To the middle of the lid of the chest is fixed externally a hook with rope attached, and now a “being” (what kind of a being is immaterial to us) begins pulling at this with a constant force. The chest together with the observer then begin to move “upwards” with a uniformly accelerated motion. In course of time their velocity will reach unheard-of values—provided that we are viewing all this from another reference-body which is not being pulled with a rope.      2
       But how does the man in the chest regard the process? The acceleration of the chest will be transmitted to him by the reaction of the floor of the chest. He must therefore take up this pressure by means of his legs if he does not wish to be laid out full length on the floor. He is then standing in the chest in exactly the same way as anyone stands in a room of a house on our earth. If he release a body which he previously had in his hand, the acceleration of the chest will no longer be transmitted to this body, and for this reason the body will approach the floor of the chest with an accelerated relative motion. The observer will further convince himself that the acceleration of the body towards the floor of the chest is always of the same magnitude, whatever kind of body he may happen to use for the experiment.      3
        Relying on his knowledge of the gravitational field (as it was discussed in the preceding section), the man in the chest will thus come to the conclusion that he and the chest are in a gravitational field which is constant with regard to time. Of course he will be puzzled for a moment as to why the chest does not fall in this gravitational field. Just then, however, he discovers the hook in the middle of the lid of the chest and the rope which is attached to it, and he consequently comes to the conclusion that the chest is suspended at rest in the gravitational field.      4
         Ought we to smile at the man and say that he errs in his conclusion? I do not believe we ought if we wish to remain consistent; we must rather admit that his mode of grasping the situation violates neither reason nor known mechanical laws. Even though it is being accelerated with respect to the “Galileian space” first considered, we can nevertheless regard the chest as being at rest. We have thus good grounds for extending the principle of relativity to include bodies of reference which are accelerated with respect to each other, and as a result we have gained a powerful argument for a generalised postulate of relativity.      5
          We must note carefully that the possibility of this mode of interpretation rests on the fundamental property of the gravitational field of giving all bodies the same acceleration, or, what comes to the same thing, on the law of the equality of inertial and gravitational mass. If this natural law did not exist, the man in the accelerated chest would not be able to interpret the behaviour of the bodies around him on the supposition of a gravitational field, and he would not be justified on the grounds of experience in supposing his reference-body to be “at rest.”      6
          Suppose that the man in the chest fixes a rope to the inner side of the lid, and that he attaches a body to the free end of the rope. The result of this will be to stretch the rope so that it will hang “vertically” downwards. If we ask for an opinion of the cause of tension in the rope, the man in the chest will say: “The suspended body experiences a downward force in the gravitational field, and this is neutralised by the tension of the rope; what determines the magnitude of the tension of the rope is the gravitational mass of the suspended body.” On the other hand, an observer who is poised freely in space will interpret the condition of things thus: “The rope must perforce take part in the accelerated motion of the chest, and it transmits this motion to the body attached to it. The tension of the rope is just large enough to effect the acceleration of the body. That which determines the magnitude of the tension of the rope is the inertial mass of the body.” Guided by this example, we see that our extension of the principle of relativity implies the necessity of the law of the equality of inertial and gravitational mass. Thus we have obtained a physical interpretation of this law.      7
           From our consideration of the accelerated chest we see that a general theory of relativity must yield important results on the laws of gravitation. In point of fact, the systematic pursuit of the general idea of relativity has supplied the laws satisfied by the gravitational field. Before proceeding farther, however, I must warn the reader against a misconception suggested by these considerations. A gravitational field exists for the man in the chest, despite the fact that there was no such field for the co-ordinate system first chosen. Now we might easily suppose that the existence of a gravitational field is always only an apparent one. We might also think that, regardless of the kind of gravitational field which may be present, we could always choose another reference-body such that no gravitational field exists with reference to it. This is by no means true for all gravitational fields, but only for those of quite special form. It is, for instance, impossible to choose a body of reference such that, as judged from it, the gravitational field of the earth (in its entirety) vanishes.      8
            We can now appreciate why that argument is not convincing, which we brought forward against the general principle of relativity at the end of Section XVIII. It is certainly true that the observer in the railway carriage experiences a jerk forwards as a result of the application of the brake, and that he recognises in this the non-uniformity of motion (retardation) of the carriage. But he is compelled by nobody to refer this jerk to a “real” acceleration (retardation) of the carriage. He might also interpret his experience thus: “My body of reference (the carriage) remains permanently at rest. With reference to it, however, there exists (during the period of application of the brakes) a gravitational field which is directed forwards and which is variable with respect to time. Under the influence of this field, the embankment together with the earth moves non-uniformly in such a manner that their original velocity in the backwards direction is continuously reduced.”   

[mad aetherist (OP)]

In trying to support this contention, he imagined a large closed chest which was first at rest on the surface of a large body like the Earth, and then later removed to a great distance from other matter where it was pulled by a rope until its acceleration was g . No experiment made inside could, he claimed, detect the difference in the two cases.

Einstein imagined a small chest, not a large one.  He asserted that no local experiment could detect the difference.  Putting two plumb lines a foot apart with instruments sufficiently sensitive to detect the angle constitutes a non-local test.

Alby said (English translation)........      As reference-body let us imagine a spacious chest resembling a room with an observer inside who is equipped with apparatus.

[mad aetherist (OP)]

Alby said (English translation)........      As reference-body let us imagine a spacious chest resembling a room with an observer inside who is equipped with apparatus.

So he did.  For proper equivalence, let us put the room with the gravity in a chamber underground, as Evan suggests.  Then your plumb-line test isn't going to be able to tell the difference. The room can be as large as you like now.

I fear that u are now making a mistake that i made earlier that u quite rightly corrected me on. 
I said that if the gravity field was uniform (g constant in time & constant in the xyz of the chest-elevator-room) then the 2 or 4 strings would not hang proper but would just float around.
Based on the original OP being about Brown doing his test(s) above ground (ie at the surface), ie gravity field super-uniform (g constant in xy horizontal plane but decreasing with height in the z vertical direction).  U pointed out that even if that Brownian test were done in a shaft underground (gravity field sub-uniform)(g constant in the xy horizontal plane but increasing with height in the z vertical direction) the strings (or plumb-line if u like) would nonetheless hang straight (down)(albeit a little less tight).  And u were correct. 
My error was partly due to semantics re the definition of a uniform field (i didnt say so but i had pictured an aetheric analogy that was wrong)(it was an analogy of a different circumstance)(partly due to semantics).

I dont see how doing Brown's test in a chest-elevator-room in a chamber underground would make any difference to doing it in a shaft underground as already mentioned.  Even if the chamber were very large, & even if the chamber were located as deep as u want (but of course not at center of Earth). 
Above ground g varies more or less linearly & slowly, decreasing with height.
Below ground it can according to wiki vary more strongly & at some depths increasing & at some depths decreasing, & at some depths can be uniform (constant is a better term).
But nonetheless a pair of strings spaced a small distance apart & well away from side-walls will hang down non-parallel, & then when moved a little further apart & still well away from side-wall will be seen to hang either more parallel or less parallel, & this will tell Igor whether he is in a gravity field or in an acceleration field, & Brown's string test will work ok in most locations in or on Earth (if in a gravity field)(even if in a big underground chamber), & will work ok in deep outer space well away from mass (if in an acceleration field).
What am i missing?

Ah i just then saw the posting by Colin2B (i thort u said it was by Evan). Colin said.......
Sorry, I should have been more specific, I didn’t mean a cavity centred on the sphere’s centre, but one offset from the centre. Don’t have time to do the tex (too much spam around at moment). I think @PmbPhy might have it on his website. It is also possible to envisage an area on earth where the geoid, due to density variation below the surface, becomes flat over a limited area and plumb lines over that area would be parallel.
It looks to me that Colin is making the same mistake that u corrected me on.
If there is a depth where the geoid becomes flat then in fact the geoid would have a fuzzy surface.

[mad aetherist (OP)]

But nonetheless a pair of strings spaced a small distance apart & well away from side-walls will hang down non-parallel
What am i missing?

No they won't.  Each string will be more attracted to the more nearby mass on it's own side, and this outward pull will bring the two plumb lines back into parallel.

Yes, but i did say well away from the side-walls. If u like u can have very light walls & very heavy string (or heavy bobs). Or how about just have a spherical elevator, then u can hang the strings anywhere u like.

If there is a depth where the geoid becomes flat then in fact the geoid would have a fuzzy surface.

No idea what you mean by it having a fuzzy surface.

If the zone of uniform or constant g is say 10 km deep then the geoid can be drawn to pass throo anywhere u like in that 10 km. Or it can be drawn to pass throo everywhere in that 10 km, in which case u will have lots of lines, or in effect a fat fuzzy line.

[guest4091]

But nonetheless a pair of strings spaced a small distance apart & well away from side-walls will hang down non-parallel
What am i missing?

No they won't.  Each string will be more attracted to the more nearby mass on it's own side, and this outward pull will bring the two plumb lines back into parallel.

Gravitational force depends on the distribution of mass. In the case of a sphere, it's equivalent to the mass being concentrated at the center. As one test mass moves away from the other around the sphere the g-force direction always points to the center, thus the angle between the string supports must  increase as they separate.

[mad aetherist (OP)]

Gravitational force depends on the distribution of mass. In the case of a sphere, it's equivalent to the mass being concentrated at the center. As one test mass moves away from the other around the sphere the g-force direction always points to the center, thus the angle between the string supports must  increase as they separate.

Take it up with Colin2B, from post 42 where this was pointed out.
Mass of a perfect sphere is concentrated nowhere.  It is assumed to be a uniform density sphere, which of course the Earth is not. It is neither uniform density nor an actual sphere. We're talking about an ideal scenario here.

A hollow shell will behave from the outside as a point-mass centered on the sphere, but from inside that hollow, the field is unform, and a plumb-line hung from anywhere will have no force at all on it.  Put the hollow off-center, and the force now appears, but still uniform/parallel.

I dont  think that Brown's string test needs an ideal spherical Earth, almost any roundish blob will do, but of course a sphere is best.
Phyti is of course merely referring to Brown's test, Phyti pointing out that Brown's test is legit, the strings when moved a bit further apart in a gravity field (near Earth)(or near a perfect sphere) will point less parallel. Phyti is not making a comment on my idea of having a spherical elevator-chest-box.

[mad aetherist (OP)]

But nonetheless a pair of strings spaced a small distance apart & well away from side-walls will hang down non-parallel
What am i missing?

No they won't.  Each string will be more attracted to the more nearby mass on it's own side, and this outward pull will bring the two plumb lines back into parallel.

Gravitational force depends on the distribution of mass. In the case of a sphere, it's equivalent to the mass being concentrated at the center. As one test mass moves away from the other around the sphere the g-force direction always points to the center, thus the angle between the string supports must  increase as they separate.

I notice in my OP that Brown did say a large chest, the inference being that the test with the pendulums being 1 foot apart is well clear of the gravity of the walls, but Brown doesnt actually say so.
I notice that Brown was in fact referring to two simple pendulums, ie a wt on the end of a string, whereas i have been referring to strings with no wt on the end.  Anyhow even in a simple chest the walls would not be an issue if the wts were massive enuff (but might destroy the ceiling).

[mad aetherist (OP)]

Brown's twin-pendulum test of equivalence is just one of many tests that can disprove Einstein's chest-elevator equivalence thort-X. If an Einsteinian comes up with a scenario where one particular test wouldnt disprove then that is not fatal to the anti-Einsteinians -- one of the other tests will be sure to work in that scenario -- but in any case all that an anti-Einsteinian need do is to find just one chest-elevator scenario where just one test can distinguish tween gravity & acceleration and equivalence is proven wrong (end of argument).

And i notice that almost everyone looking into this equivalence stuff falls back on the two standard scenarios, eg an elevator sitting motionless in a gravity field & an elevator being accelerated upwards. But any sort of elevator scenario should be ok.  For example i can disprove equivalence by simply considering a test or two in an elevator in freefall in a gravity field versus an elevator in freefall in zero gravity.

When i say that i can disprove equivalence i dont mean that i can disprove the law of equivalence of inertial mass & gravitational mass -- that cant be done -- inertial mass is numerically equal to gravitational mass (at least it is in the macro world, but not in the micro world)(& there are subtle differences that can come into play in some instances).
No, the disproof applies to the notion that gravity is equivalent to acceleration. It might be in many instances but aint in many important instances (for example re the bending of light).

[mad aetherist (OP)]

For example i can disprove equivalence by simply considering a test or two in an elevator in freefall in a gravity field versus an elevator in freefall in zero gravity.

Without designing an experiment that detects non-uniformity of the gravitational field?  That's effectively looking out of the window, and nobody claims you can't tell if there is a window. Have at it, so I can take it apart.

I havent thort of looking out of a window. I am not sure whether that would make it easier.  But one version of the light beam thort-X that i have seen has the beam entering throo a window.

(A) Anyhow i reckon that in an elevator in free fall...
(1) In free-fall in deep outer space a beam of light from a distant star entering a small hole would remain straight (& hit the far wall).  This is based on this being a ballistic Newtonian bending (which cancels the bending due to free-fall).
(2) In free-fall in a gravity field (near a planet) the beam would curve (& hit the far wall). This is based on an Einsteinian bending which is twice the Newtonian. 
So here the observer would be able to tell whether in a gravity field based on there being a curve or not.
 
(B)  If the Einsteinian bending = the Newtonian bending then the beam might be straight in both (2) &(1).
But in (1) the individual photons would remain pointing in line with the beam at all times,  whilst
in (2) the photons would gradually yaw (in the vertical plane) & would be crabbing along the line of the beam & would be pointing on a different vertical angle to the beam especially at the end (the curved beam being their traject).

(C)  If an Einsteinian plead that both (1) & (2) would produce a curved beam then i would point out that 
in (1) the individual photons would retain their initial direction of pointing (in the vertical plane) all of the way across the elevator, whilst crabbing along the line of trajectory of the beam &
in (2) the photons would gradually yaw (in the vertical plane) such that their pointings would follow the curved line of the beam all of the way across & they would not exhibit any crabbing at any time.

Re yawing & pointing, there is no real need to insist on having any beam curving in some sort of vertical plane (there is no vertical in free-fall anyhow), the curving yawing pointing can be allowed to happen in any plane, doesnt really matter.  I just mentioned the vertical because yawing is usually associated with the horizontal plane, but if there is any curving then the yawing & pointing will occur in the plane of the curving.

[mad aetherist (OP)]

Anyhow i reckon that in an elevator in free fall..
(1) In free-fall in deep outer space a beam of light from a distant star entering a small hole would remain straight (& hit the far wall).  This is based on this being a ballistic Newtonian bending (which cancels the bending due to free-fall).

Not a local test.  You're looking out of the window.

If u like u can shine a light beam from wall to wall inside. Possibly the same thing.
[17dec2018-- I AM FAIRLY CERTAIN THAT EINSTEIN HAD A RAY OF LIGHT ENTERING HORIZONTALLY AT THE MIDDLE OF ONE WALL.]

(2) In free-fall in a gravity field (near a planet) the beam would curve (& hit the far wall). This is based on an Einsteinian bending which is twice the Newtonian.
So here the observer would be able to tell whether in a gravity field based on there being a curve or not.

A legit test, but both should be straight.  So where do you get this "Einsteinian bending which is twice the Newtonian"?

I thort that Einsteinians all agreed that the bending at the Sun is 1.75 arcsec whilst the Newtonian ballistic prediction is 0.875 arcsec, which is in effect 2:1.  But i am surprised that u consider that both should be straight, i would have thort that Einsteinians would insist that both be curved.

If the Einsteinian bending = the Newtonian bending then the beam might be straight in both (2) &(1).
But in (1) the individual photons would remain pointing in line with the beam at all times,  whilst
in (2) the photons would gradually yaw (in the vertical plane) & would be crabbing along the line of the beam & would be pointing on a different vertical angle to the beam especially at the end (the curved beam being their traject).

I'm sorry, but the English is so poor here, I cannot parse this.  No idea what 'crabbing' is, or what it would mean for a photon to 'yaw' or 'point', or for that matter what you think would cause it to do so.  Photons get measured when the interact with something. Yaw means that the thing twists sideways while moving, but without changing trajectory, sort of like a car sliding sideways on the ice.

Yes yaw is a rudder thing. If one considers that a photon is shaped like a bullet then in (1) the bullet follows a straight traject & at all times the bullet maintains its initial "aim" or "heading", ie it points in the same direction all the way, ie in this case it points exactly along its straight traject all the way, whilst in (2) the bullet follows a straight traject but the bullet as u say slides sideways (crabs), the crabbing getting worse & worse & being at a max when it hits the wall.

Re yawing & pointing, there is no real need to insist on having any beam curving in some sort of vertical plane (there is no vertical in free-fall anyhow), the curving yawing pointing can be allowed to happen in any plane, doesnt really matter.  I just mentioned the vertical because yawing is usually associated with the horizontal plane, but if there is any curving then the yawing & pointing will occur in the plane of the curving.

No matter which plane it is.  I claim any beam appears to be straight for both observers.
If there is a gravity field, I suppose that defines which way is vertical even in free fall, even if the observer cannot detect it.  You are free to talk about it.
If the observer can determine which way is vertical with a local test, that's something the guy in space cannot do, so that would be a distinction.

If the beam is straight then if the photon-bullet is at all times in line with the beam then that indicates no gravity field -- or if the photon-bullet is crabbing-skidding then that indicates the presence of a gravity field, & the common plane of the photon-bullet's centerline & the line of the beam indicates the plane that contains the line of action of the gravity field -- & the general direction of the nose of the photon-bullet indicates the general direction -- but the exact line of action of the field might not be determinable (there might be some other test that helps here).
But i am surprised that u went for (B), i thort Einsteinians would go for (A). I modified my earlier thread, there is also a (C).

[mad aetherist (OP)]

If u like u can shine a light beam from wall to wall inside. Possibly the same thing.

That's fine.  The beam should be measured by the observer to go straight across in both cases.
Comment: I think that it is ok to insist on non-local inputs. However in the case of my far-away starlight i think that that should be acceptable, after all i am only using it to provide a constant (& a straight & aligned photon) photon input, its not as if i am checking on its frequency or something.
Re the beam going straight across in both cases -- i will address this in its own posting later today.
[17dec2018-- I AM FAIRLY CERTAIN THAT EINSTEIN HAD A RAY OF LIGHT ENTERING HORIZONTALLY AT THE MIDDLE OF ONE WALL.]

I thort that Einsteinians all agreed that the bending at the Sun is 1.75 arcsec whilst the Newtonian ballistic prediction is 0.875 arcsec, which is in effect 2:1.

Yes.  Newton was wrong.  There is no Newtonian bending.
Comment:  Einstein in 1911 got 0.83~0.875 arcsec for bending due to time (the time in spacetime) & in 1915 added 0.87~0.875 arcsec for space (the space in spacetime) to get  1.7~1.75 arcsec.  Soldner got 0.83~0.875 arcsec in 1805 (?) using a ballistic calculation, which we call the Newtonian value.  The 0.875 arcsec & 1.75 arcsec are using modern numbers for Sun's mass & G etc.  Yes i think that Einstein didnt directly include any Newtonian-ballistic bending in his figures (but praps indirectly), & the Soldner 0.83~0.875 arcsec might be a co-incidence (or it might be an automatic outcome what with Einstein's stuff riding on the back of Newton's stuff).

But i am surprised that u consider that both should be straight, i would have thort that Einsteinians would insist that both be curved.

Not from the frame of either observer in either box.
Comment: I will address this later today..

Yes yaw is a rudder thing. If one considers that a photon is shaped like a bullet then in (1) the bullet follows a straight traject & at all times the bullet maintains its initial "aim" or "heading", ie it points in the same direction all the way, ie in this case it points exactly along its straight traject all the way, whilst in (2) the bullet follows a straight traject but the bullet as u say slides sideways (crabs), the crabbing getting worse & worse & being at a max when it hits the wall.

Photons don't have a shape, and don't yaw. 
Comment:  This is the crux of the issue.  I will address this in a separate posting later today.
They are measured at certain points, which in this case will be a spot on the wall directly opposite the source of the light.  If it is a beam, it might be measured in the path between as it is defected by dust and such.  That beam will be observed to be straight in this freefall case.
Comment:  Yes measurements at various points will show whether straight or curved.

If the beam is straight then if the photon-bullet is at all times in line with the beam then that indicates no gravity field -- or if the photon-bullet is crabbing-skidding then that indicates the presence of a gravity field

If you're going to propose this, you're going to have to indicate how one might measure the way a photon points at the event of measurement.  One can only measure a photon once, per Heisenberg. From my point of view, you're making up total fiction.   
Comment:  Yes i dont know how we might measure which way a photon is pointing (ie whether it is crabbing), especially with ultra-small values. I will think about this & address it separately later today.
The measurement would of course be made at the far wall. If photons are destroyed during measure then that aint a worry.  Heisenberg's stuff is nonsense (but not relevant here)(& not relevant anywhere else).  The fiction is Einstein's, as i will show.