Index lower-bound conjecture for branched CMC immersions

About 2 years old · traced to

Let u:Σ2→N3u:\Sigma^2\to N^3 be a branched CMC hh-immersion, where N3N^3 has strictly positive sectional curvature, and let gg denote the genus of Σ\Sigma. Write iAhi_{\mathcal{A}_h} and nAhn_{\mathcal{A}_h} for the index and nullity of the relevant constrained second-variation operator. Index lower-bound conjecture. There exists a constant C=C(N)<∞C=C(N)<\infty such that

C((1+h2)Area⁡(Σ)+g)≤iAh+nAh.C\left((1+h^2)\operatorname{Area}(\Sigma)+g\right)\leq i_{\mathcal{A}_h}+n_{\mathcal{A}_h}.

For N=R3N=\mathbb{R}^3 or N=T3N=T^3 a flat three-torus, the analogous expected bound is

C(h2Area⁡(Σ)+g)≤iAh+nAh.C\left(h^2\operatorname{Area}(\Sigma)+g\right)\leq i_{\mathcal{A}_h}+n_{\mathcal{A}_h}.

The conjecture asserts that the index plus nullity is bounded below linearly by the Willmore-type energy and genus, complementing known index lower bounds in terms of genus. The stated flat-ambient version is presented as an expectation rather than an asserted theorem, and the source gives no resolution.

References

Primary source

Luca Seemungal and Ben Sharp, “Index estimates for constant mean curvature surfaces in three-manifolds by energy comparison”, arXiv:2411.02932 (2026).

Progress summary

Never refreshed

Nothing recorded yet. Refresh searches the literature and the public web for attempts on this problem, and writes the first summary here.

Solutions 0

No solutions have been posted yet.