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On the Plants Leaves Boundary, "Jupe à Godets" and Conformal Embeddings

Sergei Nechaev·Raphael Voituriez
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Abstract

The stable profile of the boundary of a plant's leaf fluctuating in the direction transversal to the leaf's surface is described in the framework of a model called a "surface à godets". It is shown that the information on the profile is encoded in the Jacobian of a conformal mapping (the coefficient of deformation) corresponding to an isometric embedding of a uniform Cayley tree into the 3D Euclidean space. The geometric characteristics of the leaf's boundary (like the perimeter and the height) are calculated. In addition a symbolic language allowing to investigate statistical properties of a "surface à godets" with annealed random defects of curvature of density $q$ is developed. It is found that at $q=1$ the surface exhibits a phase transition with critical exponent $α=1/2$ from the exponentially growing to the flat structure.

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Sergei Nechaev, Raphael Voituriez. 2001-11-19. On the Plants Leaves Boundary, "Jupe à Godets" and Conformal Embeddings. https://doi.org/10.1088/0305-4470%2F34%2F49%2F322

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