On J. C. C. Nitsche type inequality for annuli on Riemann surfaces

David Kalaj

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arXiv · 1204.5419

On J. C. C. Nitsche type inequality for annuli on Riemann surfaces

David Kalaj

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Abstract

Assume that $(\mathcal{N},\hbar)$ and $(\mathcal{M},\wp)$ are two Riemann surfaces with conformal metrics $\hbar$ and $\wp$. We prove that if there is a harmonic homeomorphism between an annulus $\mathcal{A}\subset \mathcal{N}$ with a conformal modulus $\mathrm{Mod}(\mathcal{A})$ and a geodesic annulus $A_\wp(p,ρ_1,ρ_2)\subset \mathcal{M}$, then we have ${ρ_2}/{ρ_1}\ge Ψ_\wp\mathrm{Mod}(\mathcal{A})^2+1,$ where $Ψ_\wp$ is a certain positive constant depending on the upper bound of Gaussian curvature of the metric $\wp$. An application for the minimal surfaces is given.

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David Kalaj. 2012-04-27. On J. C. C. Nitsche type inequality for annuli on Riemann surfaces. https://arxiv.org/abs/1204.5419

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