A Context for Manifold Calculus
Kensuke Arakawa
TL;DR
This work extends Weiss's manifold calculus to ∞-categories with small limits, introducing $k$-excisive (polynomial) and good functors and constructing universal polynomial approximations $T_kF$ via left Kan extensions. It provides a full classification of homogeneous degree-$k$ functors in terms of configuration spaces $B_k(M)$ and the functor $Sing\,B_k(M)$ when the target is pointed, recovering the classical Weiss classification in spaces and generalizing to arbitrary targets such as spectra or chain complexes. The Taylor tower framework is developed through Taylor cotowers, with convergence criteria tied to excisivity, exhaustivity, and analyticity, including connectivity results in the presence of a t-structure. The paper then extends these ideas to context-free manifold calculus and to the boundary case, showing that the same structural picture—polynomial approximations, tower convergence, and homogeneous classification—persists under appropriate replacements of disks, opens, and fat diagonals. Collectively, the results provide a flexible, ∞-categorical foundation for manifold calculus applicable to diverse targets and to invariants arising in factorization homology and related theories.
Abstract
We develop Weiss's manifold calculus in the setting of $\infty$-categories, where we allow the target $\infty$-category to be any $\infty$-category with small limits. We will establish the connection between polynomial functors, Kan extensions, and Weiss sheaves, and will classify homogeneous functors. We will also generalize Weiss and Boavida de Brito's theorem to functors taking values in arbitrary $\infty$-categories with small limits.
