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Jim:

As I pointed out in my earlier post, if you are, indeed, restricting yourself to distinguishing between behaviors of free neutral test particles within a box in geodesic motion ("free fall") vs. a box experiencing "inertial acceleration" (deviating from geodesic motion), then you are presenting nothing new, etc.

One of the reasons I insist that all your terms be strictly defined, or "nailed down", is because of the way you try to weasel out of any argument by apparently changing the definitions on a whim (changing the rules).

I "gravitate" to distinguishing between geodesic vs. non-geodesic motion because it is well defined (determinable, at least in principle) in all cases (regardless of the nature of the curvature, or lack thereof). The only "difficulty of determining in some cases, by observation, whether a body is deviating from geodesic motion" is in terms of experimental accuracy, as with any observational measurement. One has the same difficulty if your "inertial acceleration" of the box is arbitrarily small. So what? We're talking thought experiments here, so that's why I often say that such is at least theoretically, or in principle, always decidable.

I'm not arguing, in any way, that the situation of the box undergoing geodesic motion vs. the box deviating from geodesic motion is not distinguishable (except to the limits of instrumentality, which have far tighter limits than anyone's eyes). I'm simply arguing that this is nothing new. This is why Einstein's thought experiments focused on more novel situations.

Your point 1 is nothing new, novel, etc.

Your point 2 looses almost all it's power because it is not general enough. I have tried to help you see how this can be completely generalized (up to a point), depending on how you wish to "define" the "existence" of a "gravitational field". Unfortunately, instead, you have tried to weasel out of definitions. You have refused to learn greater generalizations. You simply don't appear able to move from your comfort zone in the very specialized subset of circumstances you find on and very near this ball of rock we reside upon, while the universe is far more vast and wondrous. (If you desire, I, and others, can help you take off your blinders, but we can't force you.)

In my very first post to you I attempted to show you that there is indeed a sense in which gravitation is not a force. However, there are indeed ways of looking at things such that it is, at least as much as any other inertial (pseudo, "false") "force" may be considered to be a "force". (Note that these "inertial forces" are not related to your "inertial acceleration". This was one of the early problems in definition that lead to misunderstandings, so please don't confuse them now. I, at least, have never seen the term "inertial force" used to describe any "true" forces like springs, electromagnetic forces, etc.)

Indeed, on the other hand, there are ways of approaching all the "true" forces (electromagnetism [which includes contact forces, since it is only E&M that keeps objects more or less rigid, and keeps them from moving through one another], and the nuclear forces [week and strong]) such that they are just as much "geometry" as is gravitation. What then? Now what appear to be deviations from geodesic motion (deviations from "free fall") are simply new geodesics seen by certain types of particles. (Is this the way the universe works, or just a mathematical trick we physicists have dreamed up? Only specific testable predictions and experiments will ever determine that.)

Never, at any point do I propose "presume[d] phenomena" that are "inconsistent with [the appropriately generalized] points 1 and 2".

I have tried to help you put your arguments in a much broader perspective, and to refine them to the point that (up to a point*) they are irrefutable. Unfortunately, instead of cooperating, learning, and refining, you have chosen to cast me in the role of your enemy, nemesis, and a "defender of the faith".

I'm not going to just give you the answer, you have to want it, and be prepared for it.

So long, and fare well.

David

* After asserting that gravitation is not a force (an assertion I tried to point out, in my first post, is indeed justifiable, even though there are alternate, legitimate, view points), there are certain conclusions you arrive at, without justification, that are untenable. At least if the results/predictions of General Relativity are correct (as opposed to just certain interpretations, or ways of thinking about its nature).

You claim that you have no argument with the theory, itself, just certain interpretations, or ways of thinking about General Relativity. Yet, without justification, you jump from the conclusion that "gravity is not a force", to "gravity has no energy" (in and of itself), to "there are no gravitational waves".

Especially the last part of this chain is untenable, unless one argues that the results/predictions of General Relativity are not correct. This is the point where your arguments cannot be made irrefutable.