Existing very high levels of biological complexity in the universe (us for example) imply very sophisticated engineering, both in the structure of the universe, and in the way it has been modified by its servomechanism, life to perform specific functions.

In the 7-D universe, what we call "Birth" and "Death" are really kinds of time travel...the purpose of which (if there is a purpose) is unknown.

The implications of extremely high biological complexities existence in the universe are profound, and deserve careful reflection. One of these implications is that ALMOST everything which can be done engineering wise, HAS been done, and is a part of cosmic existence at some coordinates.

Another implication is that this universe is NOT pantheistic. Our universe is far too structured and hierarchical for that,in fact the reality we observe implies a monarchy, benevolent (our life is a gift), merciful (redundant systems) but strict (once you actually reach a certain point you don't and perhaps better, can't change your mind). A homogenous universe of dispersed energy could more easily be described as pantheistic.

Time travel only makes sense in a hierarchical heterogeneous, and ordered universe with a multitude of possible destinations anyway.

A failure to come to grips with the real significance and profound implications of low entropy and complex organization, both in the actual structure of the universe, and ourselves, can result in philosophical vertigo.

The metaphysical implications of SRT and GR are an indication of their veracity, or at least imply they are taking us in the right direction conceptually, because the universe definitely has a profound metaphysical component...it is rational, yes, but it is also profound and very complex.

By the way, I'd be careful about divorcing SRT from GR conceptually. I can live with handling QM as a separate issue, but the mathematical GR model gets very "sticky" at scales near the macroscopic and microscopic antipodes.

Your "superluminal" velocity assertions are an example of the curve-balls generated by divorcing the two concepts. In the photon universe, communication is instantaneous. This SRT concept reflects an aspect of GR you discuss as "superluminal", but your discussion of the reference frame aspect of that subject is inadequate- and in GR, invariant reference frames are the key to concept.

I say future concepts will "build" on GR. We still have a lot to learn! Extrapolation is fun- and possible in GR. We might even learn profound truth about the universe by following that route, however the speed of light in a vacuum has been shown to be invariant to, what is it?...10 places? We also need to remind ourselves from time to time of the conceptual kinship of SRT and GR.

Best Wishes, Sam Cox