The Bishop family of holomorphic discs: regularity and higher index

Brendan Guilfoyle; Wilhelm Klingenberg

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arXiv · 2608.21068

The Bishop family of holomorphic discs: regularity and higher index

Brendan Guilfoyle·Wilhelm Klingenberg

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Abstract

We prove $C^{k/2,\alpha/2}$ -regularity up to a non-umbilic elliptic complex point for the Bishop family of holomorphic discs with boundary in a $C^{k,\alpha}$ regular real surface. Furthermore, we prove existence and regularity of holomorphic discs near certain complex points of index $\ge 2$. The proof employs a novel blow-up of the real surface which resolves the complex point to a pair of totally real surfaces and leads to a $\mathbb{Z}_2$ -equivariant Riemann-Hilbert problem for holomorphic annuli. The index is computed to be 1 and the problem is shown to be Fredholm-regular.

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Brendan Guilfoyle, Wilhelm Klingenberg. 2026-08-21. The Bishop family of holomorphic discs: regularity and higher index. https://arxiv.org/abs/2608.21068

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