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David,

I think if I’ve been “absolute” you’ve been “relativistic” (in the philosophical sense). You write that “‘quantum theory' is far from a singular. In fact it's something more like a theory of theories…. So it's rather difficult, if not impossible, to characterize 'quantum theory' as treating gravity as or not as a 'force', of some kind.”

If there’s some school of quantum physics which holds that it’s unjustifiable to consider gravitation a force, or to believe a gravitational wave can carry energy, I’m not aware of it. Are you? Or do you raise this as a hypothetical of the kind that would render any definite (absolute) position untenable in principle?

You wonder if I believe “if we were to cease and desist in any attempt that even smells of treating gravity as ‘force’ or related to ‘energy’, then all would be far better.” Yes.

“I'm not sure it would be proper to characterize the way [string theory] tries to incorporate gravity as ‘force’-like, except that it is a fair example of a theory/model that tries to use the success of General Relativity as a guide by trying to treat all ‘forces’ (interactions, really) as curvature (in a higher dimensional spacetime).”

My understanding of the concept of “strings” is that they are identifiable entities which embody or transmit force (choose any definition you like), which in terms of gravitational geometry I find to be wildly speculative and absolutely incoherent. (More on absolute statements below.)

“So, Jim, at this point it appears that your greatest enemy is your own predilection for "absolute" statements. Have you not learned that, especially in matters of science, such are seldom, if ever, fully valid?”

Physics is built upon mathematical statements that are absolute. The tenets of special and general relativity are expressed as absolutes. The fundamental tenets of quantum physics are absolutes. I suggest to you that we tend to find absolute statements objectionable when we are loathe to abandon the beliefs the absolutes are threatening, and we’re unable to effectively defend our beliefs directly (or absolutely), without abstract relativism or obscurantism.

I've tried to show as methodically as I can that there is no empirical or even coherent transition from the concept of gravitation as a curvature of spacetime to gravitation as a force or a carrier of energy. You've raised speculative hypotheses that presume a transition. A hypothetical presumption doesn't undermine an absolute, and it doesn't render absoluteness objectionable. I illustrated in the beginning, in a specific narrative of a thought experiment, how force enters into combination with gravitation-as-curvature. Unless a specific counter example can be offered, where gravitation itself is shown to be force-like, the distinction between gravitation and force seems absolutely clear.