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IndisputableMonolith.Gravity.SevenGaps.Gap2SizeBlindnessReach

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Establishes the reach of size-blindness for Gap 2: blindness to a feature set X forces size-blindness of every labeled weight exactly when X resolves no more than the three index counts. Introduces loopCount, an incidence invariant not fixed by those sizes, plus its disjoint-union and relabeling laws. Downstream posting-cost and inevitability modules cite it to rule out weaker sufficient premises of the blindness shape.

claimFor a complex $K$, let $\mathrm{loopCount}(K)$ be the number of edges whose two endpoints coincide. This is a function of the incidence data and is not a function of the three index sizes alone. Size-blindness of a labeled weight is forced by blindness to a feature set $X$ for every weight if and only if $X$ resolves no more structure than those three counts.

background

Gap 2 in the gravity stack concerns the gauge-counting principle $\nu = 1/|\mathrm{Aut}|$ for the physical mass class. Gap2GaugeVolume shows a gluing law forces the inverse factorial and hence gauge counting, but assumed the gluing law. The gluing-derivation line tries to derive that law rather than postulate it, following the 2026-07-28 adversarial panel route that needs a disjoint union on the carrier.

Premise (i) of that derivation is size-blindness of the labeled weight: the weight cannot see the three index sizes. A natural hope is a weaker premise of the form "the weight cannot distinguish complexes that agree on feature set $X$". This module studies when such $X$-blindness actually yields size-blindness.

The key witness is loopCount: edges with coinciding endpoints. It is built from incidence data, is invariant under relabeling, and adds under disjoint union, yet is not determined by the three index sizes. Proper edge counts and injection lemmas for left/right summand vertices support the disjoint-union calculus.

proof idea

Definition-and-lemma module, not a single theorem. It defines loopCount (and properEdgeCount) on the incidence presentation, proves loopCount equals a sum over edges of an endpoint-coincidence predicate, and establishes congruence under edgewise relabeling.

Invariance under the module's notion of complex isomorphism follows from the relabeling lemma. Disjoint-union identities use injectivity of the left/right vertex embeddings and the corresponding edge-vertex lemmas, yielding additivity of loopCount and the empty-complex base case. Those facts supply the counterexample structure: complexes agreeing on coarser $X$ can still differ in loopCount, so $X$-blindness need not imply size-blindness unless $X$ is no finer than the three counts.

why it matters in Recognition Science

Closes a premise-strength gap on the Gap 2 gluing route. Downstream Gap2PostingCostDerivation states the point directly: Gap2GluingDerivation assumes size-blindness, and this module shows no weaker premise of the form "weight cannot distinguish complexes agreeing on $X$" supplies it, because blindness to $X$ forces size-blindness for every weight exactly when $X$ resolves no more than the three counts. That rules out a weaker sufficient premise of this shape without claiming the two conditions are interchangeable.

GaugeCountingInevitableReasons imports the module into the necessary-reasons census for why richer RecognitionLedger / posting-layer structure would force the gauge-counting principle. Together with GaugeHistoryMeasure and Gap2GluingDerivation, it keeps the gluing-law derivation from silently relocating its assumptions.

scope and limits

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