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Christopher:

I don't see that you are "unwise to give my summary interpretations of Whitehead and Logunov."

I have realized that you see the "Gravity is geometry" viewpoint as "the orthodoxy". However, your other characterizations of this "orthodoxy" appear to be inapplicable (as I've tried to point out). (Perhaps I was unwise to admit to this view, though I would expect it is reasonably apparent in my other messages. I also hope it is reasonably apparent that I see these things from multiple points of view. I, like most everyone, do, however, have a particular view I "prefer".)

On the "Causality implies the Lorentz group": First, the Lorentz group stems entirely from Minkowski space (nothing new, and nothing Zeeman is denying). Second, while Minkowski type metrics ("metrics", or pseudo-metrics, with only a single eigenvalue with opposite sign to all other eigenvalues) are the only non-singular metrics that provide for causality, the "metric" of Newtonian mechanics (Galilean Relativity) also preserves causality (as anyone steeped in classical physics can tell you). Third, the Minkowski-like metric is indeed the character of the metric of General Relativity. So, just as I, and Fred, said, General Relativity fully preserves Causality locally (in fact this is the only way the Lorentz group is typically applied in physics: Global gauge groups are a bygone concept, as far as I can see). And even globally causality is only "violated" under special topological cases that can just as well trip up Special Relativity, even with it's flat Minkowski spacetime. (So what's the argument here?)*

The only way I think you can think yourself "unwise to give my summary interpretations of Whitehead and Logunov" is if you think you need to hide information in order to get me, or others, to consider your position. (Unless, I suppose, you consider that you may have too narrow an understanding of their positions to do much more than mislead [unintentionally, of course] someone like myself as to their true/full positions.)

Don't fear, I'll still be looking into this when things settle down here, as I said in my previous messages.

David

* Interestingly, while searching for a copy of Zeeman's paper that I can read (without shelling out $30+) I found an intesting abstract to an article by A. J. Briginshaw, entitled Elementary proof of Zeeman's theorem, which claims "an elementary group-theoretic proof of the theorem that global causality implies the Lorentz group." So he, at least, appears to be pushing a global application of the Lorentz group. (Unfortunately, this paper also costs $30+.)

However, as I delve further, I find the Zeeman's theorem is not concerning causality in general, but causality preserving self-transformations of Minkowski space! So it already presumes Minkowski space.

(Incidentally, I also find the theorem referred to as the Alexandrov-Zeeman theorem, so I suppose Alexandrov either contributed to, refined, or extended it; or he independently came up with an equivalent theorem at about the same time, or even earlier. I wonder whether this is the A. D. Alexandrov I have seen references to.)