Abstract
Let \((M,{\bar{g}})\) be a compact Riemannian manifold with minimal boundary such that the second fundamental form is nowhere vanishing on \(\partial M\). We show that for a generic Riemannian metric \({\bar{g}}\), the squared norm of the second fundamental form is a Morse function, i.e. all its critical points are non-degenerate. We show that the generality of this property holds when we restrict ourselves to the conformal class of the initial metric on M.
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Acknowledgements
We express our gratitude to the referee for the careful reading of this work and for their valuable observations on the class of metrics \({\mathscr {E}}^m\).
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S. Cruz has been partially supported by INdAM—GNAMPA Project 2022 “Fenomeni di blow-up per equazioni non lineari”, E55F22000270001S and by PRIN 2017JPCAPN. A. Pistoia has been partially supported by GNAMPA, Italy as part of INdAM.
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Cruz-Blázquez, S., Pistoia, A. Non-degeneracy of Critical Points of the Squared Norm of the Second Fundamental Form on Manifolds with Minimal Boundary. J Geom Anal 33, 332 (2023). https://doi.org/10.1007/s12220-023-01395-7
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DOI: https://doi.org/10.1007/s12220-023-01395-7
Keywords
- Prescribed curvature problem
- Conformal metric
- Morse function
- Second fundamental form
- Minimal boundary
- Transversality theorem