Abstract:
We study necessary and sufficient conditions for an approximately
differentiable map $f\colon\mathbb M\to\mathbb M'$ between Riemannian
manifolds to induce a bounded transfer operator of differential forms
with respect to the norms of Lebesgue spaces. As a corollary, we see
that every homeomorphism $f\colon\mathbb M\to\mathbb M'$ of class
$\operatorname{ACL}(\mathbb M)$ whose transfer operator of differential
forms with norm in $\mathcal L_p$ is an isomorphism must necessarily
be either quasi-conformal or quasi-isometric.
We give some applications of our results to the study of the
functoriality of cohomology in Lebesgue spaces.
Keywords:Lebesgue space of differential forms, distortion of a map, quasi-conformal mapping, cohomology of Riemannian spaces.