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arXiv · 2610.35571

Gradient estimates and Liouville theorems for exponentially harmonic functions

Xishen Jin·Xi Zhang
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Abstract

We study exponentially harmonic functions on complete Riemannian manifolds. Under a lower Ricci curvature bound \(\Ric_g\geq-Kg\), we first establish a local gradient estimate in terms of the oscillation. We then prove a pointwise gradient estimate for solutions bounded from one side. As an application, when \(\Ric_g\geq0\), we obtain a Liouville theorem under a one-sided sublinear growth condition. In particular, every exponentially harmonic function bounded above or below is constant.

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Xishen Jin, Xi Zhang. 2026-10-26. Gradient estimates and Liouville theorems for exponentially harmonic functions. https://arxiv.org/abs/2610.35571

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