Eigenfunctions for quasi-laplacian

TL;DR

This paper investigates eigenfunctions of the quasi-Laplacian on a singular, non-complete manifold, demonstrating that non-constant eigenfunctions are necessarily discontinuous at infinity, revealing properties of heat flow regularity.

Contribution

It provides the first analysis of eigenfunctions of the quasi-Laplacian on a singular manifold, showing their discontinuity at infinity and linking properties to the drifted Laplacian.

Findings

Non-constant eigenfunctions of the quasi-Laplacian are discontinuous at infinity.

Eigenfunctions of the drifted Laplacian are also discontinuous at infinity.

The study reveals the irregularity of heat flow on singular, non-complete manifolds.

Abstract

To study the regularity of heat flow, Lin-Wang[1] introduced the quasi-harmonic sphere, which is a harmonic map from $M=(\mathbb{R}^m,e^{-\frac{|x|^2}{2(m-2)}}ds_0^2)$ to $N$ with finite energy. Here $ds_0^2$ is Euclidean metric in $\mathbb{R}^m$. Ding-Zhao [2] showed that if the target is a sphere, any equivariant quasi-harmonic spheres is discontinuous at infinity. The metric $g=e^{-\frac{|x|^2}{2(m-2)}}ds_0^2$ is quite singular at infinity and it is not complete. In this paper , we mainly study the eigenfunction of Quasi-Laplacian $\Delta_g=e^{\frac{|x|^2}{2(m-2)}} ( \Delta_{g_0} - \nabla_{g_0}h\cdot \nabla_{g_0}) =e^{\frac{|x|^2}{2(m-2)}} \Delta_h$ for $h=\frac{|x|^2}{4}$. In particular, we show that non-constant eigenfunctions of $\Delta_g$ must be discontinuous at infinity and non-constant eigenfunctions of drifted Laplacian $\Delta_h=\Delta_{g_0} - \nabla_{g_0} h\cdot \nabla_{g_0}$ is also discontinuous at infinity.