The consciousness of an observer has such a long chain of custody in the accumulation of elements and their assimilation into an operational role that makes it rather astounding that human nature exhibits a very limited number of recognizable traits and capabilities. Yet we are essentially limited in what we can conceive of and act upon to such an extent that in reading history it often would seem that far flung events are somehow all part of a greater global trend when in fact there is no middle to exclude. Given large enough populations of limited imaginations, there is simply few enough variations on any theme of societal conduct that one group might simply be doing something in one part of the world similar to what is happening in some other part at around the same time, though each group might be following different trajectories involving non-similar causal relationships. So that disparity among limited choices is a component of the human condition which informs us in how we categorize what we perceive to be physical phenomenon which we classify through deliberations in conventions for the convenience of agreeing upon what we might be talking about. To that extent, the observer does change the outcome of any experiment, even to the degree of interpreting the function of an apparatus.
Yet transcending perception, human consciousness seems equipped to imagine an idea, a concept derivative of shared experiences. We convene to share observations and formulate ideas, and formulate operational definitions that adequately describe common occurrences. These then we argue to be physical laws, because collectively we observe them to hold true to all observed occurrences of the same sorts. Our inherent limitations might well shield us from much if not most of what has physically transpired, but that much which we do perceive and conceptualize is real enough.
Let us consider inertia for instance. We accept it as a physical property and operationally define it generically as being such that a mass in motion tends to remain in motion unless acted upon by another force, and inversely a mass at rest tends to remain at rest unless acted upon by another force. So the general definition must be a hidden variable in the correct question; "What is it about inertia that is the same thing for any mass regardless of state of motion?" That is the missing element in both General Relativity and Quantum Gravity. And that suggests that for any finite quantity of mass:energy there is some universal maximum mass density relative to that total energy of a closed system in relation to light velocity. Regards, jrc
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The observed behavior of Black Holes at the center of galaxies would seem self contradictory in that it ejects energy jets when theoretically nothing can escape its gravity. But if there exists a universal relative proportionate mass density; the upper bound of density would be relative to the total energy of the galaxy itself and that which would exceed that density bound would take the antipodal path of least resistance in ejecta. And if universal by relative proportion it could be expected to be scale independent and the relative inertial mass density upper bound at core of a particle would be proportional to the finite mass of any discrete unitary field volume.
GR assumes an average mass density in an observable boundary which of course would therefore be also a constant density across that volume. A proportionate upper density bound in a theoretical core boundary would also be a constant density but would not be an average of the total whole mass of a unitary energy field, and only a miniscule proportion of the total energy equivalence of the field mass in a tiny core volume could physically manifest a large magnitude density value proportionate to the total measurable mass. A literal quantum field particle of continuous density gradient with a finite upper bound quantity value that eliminates the infinitesimal zero point center conundrum of a mathematical singularity. The tasks of science should include discovery from what we can describe.