A smooth Reshetnyak-harmonic sphere with unbounded distortion

We construct a compact smooth Riemannian sphere and a smooth homeomorphism from the round sphere which locally minimizes Reshetnyak operator-norm-squared energy against every same-trace Sobolev competitor, but has essentially unbounded infinitesimal distortion. This gives a negative answer for the Reshetnyak member of the general-energy formulation of Meier-Vikman-Wenger Question 1.9 in the inspected arXiv:2503.08553v1, also posed as Question 1 on printed page 1625 of Oberwolfach Report 30/2025. Scalar calibration on a flat belt and a globally exact two-form calibration on conformal caps prove the unrestricted local comparisons, including competitors leaving the image patch. The map is not a global homotopy minimizer and is not Korevaar-Schoen harmonic. A separate angular-stress proof establishes the nonsharp distortion bound 4+sqrt(17) for locally Korevaar-Schoen-minimizing spheres into complete metric spaces. Its stress-zero step implies pointwise SL(2)-minimality by matrix convexity, so the established sharper Lytchak-Wenger bound also applies. The elementary constant is retained for a self-contained proof; no improved bound is claimed. Classical metric Sobolev, energy/area, Hopf/Sacks-Uhlenbeck, Lipschitz extension and calibration ingredients are credited. The bounded priority audit used 71 queries and 32 source entries, with explicit primary-text followups and metadata-only citation leads. No earlier exact match was authenticated in that inspected material, but first bibliographic priority is unresolved. The revised 2026 Meier-Vikman-Wenger journal mathematical text was inaccessible; source scope is pinned to the inspected 2025 formulation. No unchanged final wording, continued open status through 2026, first-priority or optimal-constant claim is asserted. A later source-access addendum records selected original Sacks-Uhlenbeck passages inspected through the web PDF reader, without claiming a local PDF hash. This six-page unrefereed research note is accompanied by its authored PDF/LaTeX source, unchanged historical candidate, independent analytic/computational/source/priority reviews and reproducible verification archive. The 257 exact author controls and source-free 673-check mixed replay are distinguished from the historical 675 checks with two PDF-input identity checks. Numerical diagnostics are not rigorous interval enclosures or formal proof certification. AI tools were used extensively in development, computation, verification, adversarial review and writing. Independent AI-assisted review is not independent human or journal peer review; neither has occurred. No copied third-party source documents are distributed.

Authors

Publication Details

Journal
Zenodo (CERN European Organization for Nuclear Research)
Published
2026-10-13
DOI
https://doi.org/10.5281/zenodo.23356679
Primary Topic
Geometric Analysis and Curvature Flows
Type
preprint
Controls
|||
ALL TIME
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
preprint

A smooth Reshetnyak-harmonic sphere with unbounded distortion

Kriebel Alec
Zenodo (CERN European Organization for Nuclear Research)
Geometric Analysis and Curvature Flows
preprint

A smooth Reshetnyak-harmonic sphere with unbounded distortion

Kriebel Alec
preprint en

Abstract

We construct a compact smooth Riemannian sphere and a smooth homeomorphism from the round sphere which locally minimizes Reshetnyak operator-norm-squared energy against every same-trace Sobolev competitor, but has essentially unbounded infinitesimal distortion. This gives a negative answer for the Reshetnyak member of the general-energy formulation of Meier-Vikman-Wenger Question 1.9 in the inspected arXiv:2503.08553v1, also posed as Question 1 on printed page 1625 of Oberwolfach Report 30/2025. Scalar calibration on a flat belt and a globally exact two-form calibration on conformal caps prove the unrestricted local comparisons, including competitors leaving the image patch. The map is not a global homotopy minimizer and is not Korevaar-Schoen harmonic. A separate angular-stress proof establishes the nonsharp distortion bound 4+sqrt(17) for locally Korevaar-Schoen-minimizing spheres into complete metric spaces. Its stress-zero step implies pointwise SL(2)-minimality by matrix convexity, so the established sharper Lytchak-Wenger bound also applies. The elementary constant is retained for a self-contained proof; no improved bound is claimed. Classical metric Sobolev, energy/area, Hopf/Sacks-Uhlenbeck, Lipschitz extension and calibration ingredients are credited. The bounded priority audit used 71 queries and 32 source entries, with explicit primary-text followups and metadata-only citation leads. No earlier exact match was authenticated in that inspected material, but first bibliographic priority is unresolved. The revised 2026 Meier-Vikman-Wenger journal mathematical text was inaccessible; source scope is pinned to the inspected 2025 formulation. No unchanged final wording, continued open status through 2026, first-priority or optimal-constant claim is asserted. A later source-access addendum records selected original Sacks-Uhlenbeck passages inspected through the web PDF reader, without claiming a local PDF hash. This six-page unrefereed research note is accompanied by its authored PDF/LaTeX source, unchanged historical candidate, independent analytic/computational/source/priority reviews and reproducible verification archive. The 257 exact author controls and source-free 673-check mixed replay are distinguished from the historical 675 checks with two PDF-input identity checks. Numerical diagnostics are not rigorous interval enclosures or formal proof certification. AI tools were used extensively in development, computation, verification, adversarial review and writing. Independent AI-assisted review is not independent human or journal peer review; neither has occurred. No copied third-party source documents are distributed.

Zenodo (CERN European Organization for Nuclear Research)
Geometric Analysis and Curvature Flows
AI Navigator

Ask Laika to Summarize, Analyze, and Connect papers live on the map.

Summarize Papers & Methodologies

Extract key findings, datasets, and comparative methods across publications.

Benchmark Rankings & Visual Analytics

Rank top research institutions, authors, funders, topics, and journals by Field-Weighted Citation Impact (FWCI) and paper volume with instant charts.

Connect Distant Disciplines

Bridge topological clusters on the map to find hidden collaborative intersections.