The Whitehead group construction remains AT-owned

This page proves only the handle-geometric interpretation of torsion and the presentation-relative s-cobordism theorem. The construction of $K_1(R)$, of the elementary subgroup, of the Whitehead group $\mathrm{Wh}(\pi )$, and of contraction torsion for finite based free complexes is owned by AT-22 and is consumed here without redefinition: the stable groups and the basis ambiguity $[\pm g]$ are those of Stable general linear and elementary groups for right modules, the normality of the elementary subgroup is Stable elementary matrices equal the commutator subgroup, the quotient defining $K_1(R)$ and $\mathrm{Wh}(\pi )$ and its functoriality are those of K₁ of a ring and the Whitehead group of a discrete group, and the contraction torsion of a bounded contractible finite based free complex is Finite based free complexes and contraction torsion.

In particular this page does not compute $\mathrm{Wh}(\pi )$ for any new class of groups and does not introduce a competing sign or module convention: the right-module and group-ring conventions used for handle chains are fixed by AT-22 and AT-23, and the page consumes the published nonzero class $[1-t^2-t^3]\in \mathrm{Wh}(C_5)$ instead of recomputing it.