https://neckpinch.com/authors/keita-kunikawa/New arXiv papers by Keita Kunikawa, from Neckpinch Tue, 03 Nov 2026 07:15:30 GMT https://arxiv.org/abs/2609.34291arxiv:2609.34291Mon, 28 Sep 2026 00:00:00 GMTKeita Kunikawa — We construct an embedded torus and an entire graph in ℝ⁴ whose normal bundles are initially flat but lose this property instantaneously under mean curvature flow. We also give an example showing that the parallel principal normal condition is not preserved under mean curvature flow, even though the normal bundle remains flat along the flow.Mean curvature flow https://arxiv.org/abs/2309.11882arxiv:2309.11882Thu, 21 Sep 2023 00:00:00 GMTKeita Kunikawa, Yohei Sakurai — The aim of this paper is to study almost rigidity properties of super Ricci flow whose Muller quantity is non-negative. We conclude almost splitting and quantitative stratification theorems that have been established by Bamler for Ricci flow. As a byproduct, we obtain an almost constancy for a certain integral quantity concerning scalar curvature at an almost selfsimilar point, which is new even for Ricci flow.Ricci flowScalar curvatureWeak & singular flowsStability & uniqueness https://arxiv.org/abs/2201.11361arxiv:2201.11361Thu, 27 Jan 2022 00:00:00 GMTKeita Kunikawa, Yohei Sakurai — Bamler-Zhang have developed geometric analysis on Ricci flow with scalar curvature bound. The aim of this paper is to extend their work to various geometric flows. We generalize some of their results to super Ricci flow whose Muller quantity is non-negative, and obtain Gaussian heat kernel estimates.Ricci flowHeat kernelScalar curvatureWeak & singular flows