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IndisputableMonolith.Foundation.CircleWindingChain

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Assembles the singular-simplex layer of the circle winding invariant: continuous maps from the standard 1-simplex into S¹, conversion to paths, and the induced real displacement and integer winding. Cited by the public T-1–T8 forcing spine and the T6–T8 honesty audit. Mostly definitional glue plus transport lemmas that pull path-lifting results onto singular 1-simplices.

claimSingular $1$-simplices $\sigma:\Delta^1\to S^1$ (continuous maps from the standard topological $1$-simplex $\Delta^1=\mathrm{stdSimplex}\,\mathbb{R}(\mathrm{Fin}\,2)$) are equipped with a real displacement and an integer winding by converting $\sigma$ to a path, lifting through the covering $\mathbb{R}\to S^1$, and measuring travel in $\mathbb{R}$. The once-around fundamental $1$-simplex has both faces at the chosen basepoint.

background

Recognition Science foundation work builds topological invariants on the exact Mathlib object TopCat.sphere 1, not a custom model. Upstream, the path winding module defines displacement of a path by lifting through the trigonometric covering map and proves the displacement is independent of lift choice once the start height is fixed. The lifting module supplies contractibility of simplex realization domains so unique lifts exist. The fundamental-simplex module constructs the once-around singular 1-simplex whose two faces coincide at the basepoint. The H₁ workbench targets the missing computation $H_1(S^1;\mathbb{Z})\cong\mathbb{Z}$ without yet feeding the strict T8 bridge.

This module is the chain-level glue. It presents a singular 1-simplex as a continuous map out of the standard topological 1-simplex, records the analogous 2-simplex, and identifies the unit interval with $\Delta^1$ via a homeomorphism. Paths and 1-simplices are interconverted with round-trip identities, so the path displacement and winding invariants transport cleanly to singular 1-simplices.

proof idea

Definitional module with transport lemmas, not a single deep theorem. The interval-to-simplex map identifies $I$ with $\Delta^1$ and is checked at the endpoints. Conversion functors between paths and 1-simplices are shown mutually inverse by direct evaluation. Simplex displacement and winding are defined by converting the simplex to a path and applying the upstream path-displacement equality (the central technical result of the path winding module). Face agreement for the fundamental simplex is inherited from the fundamental-simplex construction. No new covering-space analysis is performed here.

why it matters in Recognition Science

Imported by the public dual forcing surface (δ-stratified map parallel to the unified forcing chain), by the public T-1 through T8 forcing spine, and by the T6–T8 spine honesty audit. Those parents need a well-defined integer winding on singular 1-chains of the exact $S^1$ object before the eight-tick octave (T7) and the $D=3$ dimensional step (T8) can be stated without a custom circle model. The module closes the gap between path-level lifting and the singular-simplicial set, so the H₁ workbench and the T-bridge can cite a single chain-level invariant rather than ad-hoc path data.

scope and limits

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