Entropy, Rendering Capacity, and the Origin of Axiom A3: Why Does c(t) Decline? A Candidate Mechanism, Tested and Reported Honestly

Axiom A3 ("c(t) decreases monotonically over cosmic time") has always been asserted, not
derived, inherited from Paper 1's fitted power law and never independently motivated. This paper
explores whether entropy production, rather than an unexplained decline in c itself, is the more
fundamental driver: c(t) as a symptom of a shrinking rendering budget, not a free-standing
postulate. The framework combines Paper 10's "Total First Rendering" as a low-gravitational-entropy
origin state (in Penrose's sense) with Paper 7's committed/uncommitted cell bookkeeping into a
fixed holographic capacity S_max and an entropy-throttled c(t). It resolves a standing internal
contradiction in Paper 10 (gravity classified as both a topological mode and a rendering-density
effect) and offers a structural reason why α_G is the one force coupling that isn't constant while
the other three are. Tested quantitatively, the specific production law does not yet outperform
the project's existing empirical curve fits, and a direct attempt to unify the entropy driving
c(t) with the entropy setting cosmic temperature fails cleanly, showing that gravitational/
structural entropy and thermodynamic/radiation entropy are distinct quantities that cannot be
collapsed into one variable. A separate three-observable BBN convergence (helium-4, deuterium,
and neutrino decoupling all pointing to the same narrow temperature-law exponent) stands as a
genuine, unexplained empirical target for what a correct production law should predict. All
findings, including the negative ones, are reported plainly.