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Jim:

Some somewhat separate issues...

You quote me with:

... there are ways of approaching all the "true" forces (electromagnetism ..., 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.)

To which you respond with:

Well, we should await confirmation, shouldn’t we? And given the implausibility of geometric distortions that affect different particles different ways, the hypothetical mathematics needn’t divert us from real-world considerations, should it?

While you are correct that "confirmation" of testable predictions that differ from those of alternative explanations (like the "Standard Model") is an important criteria for choosing alternative theories and descriptions (as many have pointed out to you before), there is also the Occam's razor aspect of potentially choosing such a theory if it explains present measurements just as well but is simpler, or in some other way "preferable", such as due to its ability to handle circumstances outside the realm of alternatives (such as being able to be combined with General Relativity without "blowing up", for instance).

On the other hand, barring verifications of predictions that differ from alternatives, there's certainly nothing forcing anyone to abandon present models that have served us so well. (I certainly am not trying to suggest you do anything other than recognize that there are other ways of looking at such things.)

I recognize how it may appear "implausible" to have "geometric distortions that affect different particles different ways". I can agree (though I've seen how it is done both with Kaluza–Klein theory, and with a discrete spacetime model where all connections between points are geodesics and the different dynamics are due to the way different particles have different states in the fiber bundle space associated with the discrete manifold). Of course there was a time when curved spacetime was "implausible". Let alone the idea that different observers could have different times. (Of course this is to say nothing of some of the "implausible" aspects of Quantum Mechanics.)

Second, you quote me with:

... 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).

... unless one argues that the results/predictions of General Relativity are not correct. This is the point where your arguments cannot be made irrefutable.

After which you ask: "What criticisms of GR have I made that violate its confirmations? Please be specific."

I suppose by "confirmations" you are restricting yourself to the "results/predictions of General Relativity" that have already been "confirmed"/verified. To this I would answer none, since you haven't been so careless as to call into question aspects of GR that have been well verified. However, if you had included the entire quote (the second ellipses, particularly), you will note:

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 ...

Since, as you even quoted me, I'm referring to whether you have been arguing against the proposition that "the results/predictions of General Relativity are correct (as opposed to just certain interpretations, or ways of thinking about its nature)". From the following (which starts with a quote of me)

“So the point of departure is exclusively in the interpretations of GR, not in the fundamentals of the theory or its predictions. Is this correct?”

Yes, with the exception of what I consider derivative issues, the association of gravitation with force and predictions of energy-bearing grav waves, I don’t think there’s anything of practical significance that I disagree with.

it would first appear that your sole "point of departure is exclusively in the interpretations of GR, not in the fundamentals of the theory or its predictions." (Your response of "Yes".) However, you then go on to impugn the General Relativistic "predictions of energy-bearing grav waves".

Since the General Relativistic predictions of gravitational waves is fully within the theory, not based on ("derivative", or derived from) an interpretation of GR wherein there is some "association of gravitation with force" (the latter association [of gravitation with any thing referred to as a "force] seems to be what you are primarily "railing" against), then, again, I must ask whether your "point of departure is exclusively in the interpretations of GR, not in the fundamentals of the theory or its predictions", or if you also call into question at least some aspects of the theory itself.

Are you aware that if we can never detect gravitational waves that the theory of General Relativity may be in real trouble? (I'm not talking about some detection of some theoretical particles that some interpretation of some amalgamation of Quantum Mechanics and General Relativity might suppose. That's a whole other matter.) Aspects of a theory that come under some "interpretation" can never be so critical to a theory, only fundamental predictions!

From a previous post of yours, you begin by quoting me:

In addition, may I suggest that the lunar (and solar) tides are to gravity what near field effects are to electromagnetism? So we do have this large "near field" effect. What of long range "transmission" or propagation? Is this not worthy of testing?

To which you respond with:

I suppose so, although it seems implausible in the absence of any evidence for the existence of such a dichotomy, and for its apparent basis in the implicit association of gravitation with energy. If a massive local gravity wave (the moon’s orbit, for example) doesn’t produce detectable energy, and (one would expect from its effects on the oceans) a shower of related particles, why should a distant source be expected to do so?

Unfortunately, this is a little difficult to parse, especially the relevant portion (your ending question): "If a massive local gravity wave (the moon’s orbit, for example) doesn’t produce detectable energy, and (one would expect from its effects on the oceans) a shower of related particles, why should a distant source be expected to do so?" Are you suggesting that the "massive local gravity[sic] wave" in actuality "doesn’t produce detectable energy"? Or am I just parsing this incorrectly (possibly due to a misplaced coma)? Since your next parenthetical statement of "one would expect from its effects on the oceans" suggests that, possibly, you may be willing to attribute energetic influences in the lunar tides, I'm just not quite sure what this really means. (Incidentally, the [sic] is placed by "gravity wave" because "gravity waves" are something quite different from the "gravitational waves" we are, supposedly, discussiong. I know, the term "gravity wave" seems more apt, but, unfortunately, the term was already applied to something altogether different long before General Relativity came along.)

However, if I go back to my post, from which you obtained the above quote from me, we see:

To move on to another (perhaps somewhat minor) issue... You state:

I think I mentioned elsewhere that once gravitation is distinguished from inertial acceleration it becomes evident that the moon provides us with a big, slow gravity wave to study, and with very little effort. The search for virtually imperceptible gravity-waves becomes pointless. The distinction also introduces some provocative but previously not-so salient questions about the tremendous energy a moving wave/curvature can provoke (not exert), as with the ocean tides.

While it appears that you are (here) saying that you see the lunar (and solar) tides to be evidence of gravitational waves, and (essentially?) a proof(?) that energy can be "provoke[d]" thereby. The question, I suggest, still remains as to whether gravity wave "travel" through space(-time), and whether they can carry or convey energy.

In addition, may I suggest that the lunar (and solar) tides are to gravity what near field effects are to electromagnetism? So we do have this large "near field" effect. What of long range "transmission" or propagation? Is this not worthy of testing?

So, are you "saying that you see the lunar (and solar) tides to be evidence of gravitational waves, and (essentially?) a proof(?) that energy can be “provoke[d]” thereby"?

To quote you, again, from your post where you respond to the above (but only to the gravity waves "traveling" and "energy" part), beginning with a quote of me (with a great deal left out, as can be seen above):

“To move on to another (perhaps somewhat minor) issue... The question, I suggest, still remains as to whether gravity wave "travel" through space(-time), and whether they can carry or convey energy.”

I believe gravity waves “travel”, but based on the issue I’ve been trying to discuss I can see no reason why they might be thought to convey energy. A geometric distortion or curvature of spacetime so-defined is not a force, it has no intrinsic energy, although as the tides make clear, a large moving mass produces a moving distortion, or curvature, that can flux geodesics, stress molecular binding energies, and especially with fluids, result in massive kinetic energies.

It appears that you may be debating this with yourself. You appear to accept that "as the tides make clear" that a moving mass can, indeed, cause motions that can be quite energetic (when integrated over the very significant volumes affected, at least in the case of the tides). Whether one wishes to use the term "energy" in this regard is semantics. The reality is that energetic processes "happen", and are well associated with the movement of at least a nearby object.

I just have to wonder whether you understand gravitational waves from a direct application of General Relativity theory, or some source intended for the layman. I don't mean this as any sort of "put down". It simply goes back to trying to understand what you know and what background you already have.

I could certainly understand a "layman" like explanation using an "energy" (and maybe even a "force") like argument in order to try and convey the concept of gravitational waves, but I have yet to see a truly General Relativistic argument made in such terms. I don't know, I'm just trying to make sense of where you actually stand.

Any way, I'm sure this is way more than enough, for now.

Take care.

David