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Free boundary minimal disks in convex balls

  • Robert Haslhofer EMAIL logo and Daniel Ketover
Published/Copyright: October 8, 2025

Abstract

In this paper, we prove that every strictly convex 3-ball with nonnegative Ricci-curvature contains at least 3 embedded free boundary minimal 2-disks for any generic metric, and at least 2 solutions even without genericity assumption. Our approach combines ideas from mean curvature flow, min-max theory and degree theory. We also establish the existence of smooth free boundary mean-convex foliations. In stark contrast to our prior work in the closed setting, the present result is sharp for generic metrics.

Award Identifier / Grant number: DMS-1906385

Award Identifier / Grant number: DMS-2405114

Funding statement: Robert Haslhofer was partially supported by an NSERC discovery grant and a Sloan Research Fellowship. Daniel Ketover was partially supported by the NSF grants DMS-1906385 and DMS-2405114.

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Received: 2024-08-06
Revised: 2025-09-03
Published Online: 2025-10-08
Published in Print: 2025-11-01

© 2025 Walter de Gruyter GmbH, Berlin/Boston

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