Higher degree obstructions to quasiconformal equivalence

Pierre Pansu; Francesca Tripaldi

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arXiv · 2607.11331

Higher degree obstructions to quasiconformal equivalence

Pierre Pansu·Francesca Tripaldi

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Abstract

Pairs of diffeomorphic Riemannian manifolds are shown not to be quasiconformally equivalent, while no degree one invariant (extremal lengths, conformal parabolicity,...) can distinguish them. The obstruction arises from conformal cohomology in degree 2. Similar examples are constructed in the contact subRiemannian category

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Pierre Pansu, Francesca Tripaldi. 2026-07-13. Higher degree obstructions to quasiconformal equivalence. https://arxiv.org/abs/2607.11331

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