Modulus of elementary domains in the hyperbolic plane

Ioannis D. Platis

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arXiv · 2512.00358

Modulus of elementary domains in the hyperbolic plane

Ioannis D. Platis

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Abstract

We study the modulus of curve families inside elementary domains of the hyperbolic plane $\mathbb{H}^1_\mathbb{C}$. We establish exact expressions for the modulus of connecting and separating curve families within a hyperbolic circular annulus. In contrast, for the normal hyperbolic quadrilateral, we construct sharp analytical lower bounds by restricting the metric optimisation certain subfamilies of curves, and we bracket these estimates with upper bounds using Dirichlet energy test functions. Finally, we demonstrate the barriers preventing an explicit, closed-form expression.

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Ioannis D. Platis. 2025-11-29. Modulus of elementary domains in the hyperbolic plane. https://arxiv.org/abs/2512.00358

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