We study a problem of minimal surfaces with free boundary written in the form of a non convex minimization problem. Our aim is to characterize optimal solutions by finding a suitable calibration field. A natural upper bound of the infimum is given by a variant of the Cheeger problem that we solve explicitly proving the optimality thanks to the construction of a cut-locus potential. The comparison with the original problem is then discussed in detail.

Contact details are reproduced from the original publication and may be historical.

Minh Phan

The University of Danang, University of Science and Education, Danang, Vietnam

ptdminh@ued.udn.vn
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G. Bouchitté, M. Phan. “Calibrations for Minimal Surfaces with Free Boundary and Cheeger-Type Problems.” Journal of Convex Analysis 33 (2026), No. 3&4, 691–736. https://doi.org/10.68381/jca33041