The Pontryagin-Thom theorem for families of framed equivariant manifolds
Lucas Williams
TL;DR
The paper extends the Pontryagin–Thom framework to equivariant and fiberwise settings for framed manifolds under groups G that are products of a finite group with a torus. It develops a robust equivariant bordism theory using V-framings, manifolds with corners, and genuine G-spectra, and proves an isomorphism \\omega_V^G(X,A) \\cong \\pi_V^G(\\Sigma^ olinebreak \\infty X/A). It further generalizes to families parameterized over a base B via parameterized equivariant spectra and derived section functors, yielding \\omega_V^G((X,A)\\xrightarrow{\\psi} B) \\cong \\pi_V^G(\\mathbb{R}\\Gamma_B(\\Sigma_B^ olinebreak \\infty X\\cup_A B)). The results unify geometric and homotopical perspectives in equivariant and fiberwise topology, offering a canonical bridge between framed G-bordism and equivariant stable homotopy theory with fixed-point compatibilities.
Abstract
The Pontryagin-Thom theorem gives an isomorphism from the cobordism group of framed $n$-manifolds to the $n$th stable homotopy group of the sphere spectrum. In this paper, we prove the generalization of the Pontryagin-Thom theorem for families of framed equivariant manifolds parameterized over a compact base space.
