Infinite existence of equivariant minimal hypersurfaces
Pith reviewed 2026-05-10 12:55 UTC · model grok-4.3
The pith
Closed Riemannian manifolds with isometric compact Lie group actions contain infinitely many G-invariant minimal hypersurfaces.
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
Core claim
In a closed Riemannian manifold M with an isometric action of a compact Lie group G, there exist infinitely many G-invariant minimal hypersurfaces. Under the additional assumption that M has only finitely many minimal G-hypersurfaces without a G-invariant unit normal, every G-homology class is realized by infinitely many distinct embedded minimal G-hypersurfaces. The construction proceeds via a new algorithm of multi-stage maximal cuttings inside an equivariant min-max procedure, which is also established for manifolds with cylindrical ends.
What carries the argument
multi-stage maximal cuttings algorithm that generates equivariant min-max families of G-invariant hypersurfaces
If this is right
- Infinitely many G-invariant minimal hypersurfaces exist in every such symmetric closed manifold.
- Under the finiteness assumption, each G-homology class admits infinitely many distinct embedded realizations by minimal G-hypersurfaces.
- Equivariant min-max theory extends to manifolds with cylindrical ends.
- The multi-stage cutting procedure produces families that remain invariant under the group action at every stage.
Where Pith is reading between the lines
- Symmetry constraints imposed by the group action do not reduce the total number of minimal hypersurfaces.
- The result may apply to studying minimal hypersurfaces on orbifolds obtained by quotienting by G.
- The cylindrical-end min-max theory could be tested on non-compact symmetric spaces with controlled ends.
- Concrete examples such as spheres with rotational symmetry groups could be checked to see whether the infinite families are visible by direct computation.
Load-bearing premise
M contains at most a finite number of minimal G-hypersurfaces admitting no G-invariant unit normal.
What would settle it
An explicit enumeration or construction that finds only finitely many distinct G-invariant minimal hypersurfaces in a closed manifold equipped with a nontrivial isometric compact Lie group action would disprove the claim.
read the original abstract
For a closed Riemannian manifold $M$ with a compact Lie group $G$ acting by isometries, we show that there are infinitely many $G$-invariant minimal hypersurfaces. Under the assumption that $M$ contains at most a finite number of minimal $G$-hypersurfaces admitting no $G$-invariant unit normal, we further show that each $G$-homology class of $M$ admits infinitely many distinct realizations by embedded minimal $G$-hypersurfaces. The proof relies on a new algorithm that employs multi-stage maximal cuttings. As part of this work, we also established an equivariant min-max theory in manifolds with cylindrical ends.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The paper proves that any closed Riemannian manifold M admitting an isometric action by a compact Lie group G contains infinitely many distinct G-invariant minimal hypersurfaces. Under the additional assumption that M contains at most finitely many minimal G-hypersurfaces that admit no G-invariant unit normal, the authors further show that every G-homology class of M is realized by infinitely many distinct embedded minimal G-hypersurfaces. The argument relies on a newly introduced multi-stage maximal cuttings algorithm together with an equivariant min-max theory developed for manifolds with cylindrical ends.
Significance. If the central claims hold, the work constitutes a substantial advance in equivariant geometric analysis. It extends the classical infinite-existence results for minimal hypersurfaces (Almgren–Pitts–Schoen–Simon) to the equivariant setting and supplies a new technical tool—the multi-stage cuttings algorithm—whose potential applicability extends beyond the present theorems. The construction of an equivariant min-max theory on cylindrical-end manifolds is itself a useful contribution that may be reusable in other symmetry-constrained variational problems.
major comments (2)
- The unconditional infinite-existence statement rests on the multi-stage maximal cuttings algorithm (introduced in §3 and applied in §5). Because the algorithm is new and the manuscript provides only a high-level description of its stages, a detailed verification that each stage terminates, produces embedded hypersurfaces, and generates an infinite sequence without repetition is required; without this, the reduction from the cylindrical-end min-max theory to the closed-manifold statement remains unverified.
- §6, Theorem 6.3: the stronger statement that every G-homology class contains infinitely many distinct embedded minimal G-hypersurfaces is conditioned on the finiteness assumption that only finitely many minimal G-hypersurfaces lack a G-invariant unit normal. The manuscript does not supply a criterion or example showing when this assumption holds, nor does it indicate whether the assumption is expected to be generic; this leaves the scope of the stronger result unclear.
minor comments (3)
- Notation for the G-action and the associated equivariant homology is introduced without a dedicated preliminary section; a short §2 collecting definitions, notation, and the precise statement of the G-homology groups would improve readability.
- Several figures illustrating the successive cuttings stages are referenced but not included in the provided manuscript; their addition would clarify the geometric content of the algorithm.
- The proof of the equivariant min-max theory in cylindrical-end manifolds (§4) cites several non-equivariant results without spelling out the precise modifications needed for the G-equivariant setting; a short paragraph summarizing the changes would help readers.
Simulated Author's Rebuttal
We thank the referee for the careful reading and constructive comments on our manuscript. The feedback has helped us identify areas where additional detail and clarification will improve the exposition. We address each major comment below, indicating the revisions we have made to the manuscript.
read point-by-point responses
-
Referee: The unconditional infinite-existence statement rests on the multi-stage maximal cuttings algorithm (introduced in §3 and applied in §5). Because the algorithm is new and the manuscript provides only a high-level description of its stages, a detailed verification that each stage terminates, produces embedded hypersurfaces, and generates an infinite sequence without repetition is required; without this, the reduction from the cylindrical-end min-max theory to the closed-manifold statement remains unverified.
Authors: We agree that the multi-stage maximal cuttings algorithm, being new, benefits from a more explicit verification of its properties. In the revised manuscript we have expanded Section 3 with a sequence of lemmas that establish: (i) each stage terminates after finitely many steps by a compactness argument using the isometry group and the width functional; (ii) the output at every stage is an embedded G-invariant hypersurface, obtained by applying the equivariant maximum principle to the limit of the min-max sequence; and (iii) the overall procedure produces an infinite sequence of distinct hypersurfaces, proved by contradiction via a strictly decreasing sequence of equivariant widths. These additions make the reduction carried out in Section 5 fully rigorous and verifiable from the cylindrical-end theory. revision: yes
-
Referee: §6, Theorem 6.3: the stronger statement that every G-homology class contains infinitely many distinct embedded minimal G-hypersurfaces is conditioned on the finiteness assumption that only finitely many minimal G-hypersurfaces lack a G-invariant unit normal. The manuscript does not supply a criterion or example showing when this assumption holds, nor does it indicate whether the assumption is expected to be generic; this leaves the scope of the stronger result unclear.
Authors: We acknowledge that the manuscript would benefit from a clearer discussion of the finiteness assumption in Theorem 6.3. In the revised version we have added a paragraph immediately after the theorem statement that supplies a sufficient condition: the assumption holds whenever every minimal G-hypersurface is two-sided and the G-action trivializes the normal bundle (for instance, when G acts freely). We also include a concrete example on the round 3-sphere with the standard SO(4)-action, where the only minimal G-hypersurface without an invariant normal is the equatorial S^2 (up to congruence), satisfying the finiteness requirement. While we do not claim the assumption is generic in every setting, this addition delineates the range of applicability of the stronger result. revision: yes
Circularity Check
Derivation self-contained via new algorithm and equivariant theory
full rationale
The paper claims infinitely many G-invariant minimal hypersurfaces on closed M with isometric compact G-action, proved via a newly introduced multi-stage maximal cuttings algorithm together with an equivariant min-max theory established in the work for manifolds with cylindrical ends. These tools are presented as original contributions rather than reductions of the target result to prior fitted quantities, self-citations, or definitional equivalences. The finiteness assumption on certain minimal G-hypersurfaces is explicitly restricted to a stronger statement about G-homology classes and does not enter the main existence argument. No load-bearing step reduces by construction to its own inputs or renames a known empirical pattern.
Axiom & Free-Parameter Ledger
axioms (2)
- standard math Standard axioms of Riemannian geometry and isometric actions of compact Lie groups.
- domain assumption Existence and basic properties of min-max theory for hypersurfaces.
Reference graph
Works this paper leans on
- [1]
-
[2]
Frederick Justin Almgren Jr,The theory of varifolds, Mimeographed notes (1965)
work page 1965
-
[3]
Hubert Bray, Simon Brendle, and Andre Neves,Rigidity of area-minimizing two-spheres in three-manifolds, Comm. Anal. Geom.18(2010), no. 4, 821–830. MR2765731
work page 2010
-
[4]
Bredon,Equivariant cohomology theories, Lecture Notes in Mathematics, vol
Glen E. Bredon,Equivariant cohomology theories, Lecture Notes in Mathematics, vol. No. 34, Springer-Verlag, Berlin-New York, 1967. MR214062
work page 1967
-
[5]
,Introduction to compact transformation groups, Pure and Applied Mathematics, vol. Vol. 46, Aca- demic Press, New York-London, 1972. MR413144
work page 1972
-
[6]
Otis Chodosh and Christos Mantoulidis,Minimal surfaces and the Allen-Cahn equation on 3-manifolds: index, multiplicity, and curvature estimates, Ann. of Math. (2)191(2020), no. 1, 213–328. MR4045964
work page 2020
-
[7]
Tobias H. Colding and Camillo De Lellis,The min-max construction of minimal surfaces, Surveys in differ- ential geometry, Vol. VIII (Boston, MA, 2002), 2003, pp. 75–107. MR2039986
work page 2002
-
[8]
Differential Geom.95(2013), no
Camillo De Lellis and Dominik Tasnady,The existence of embedded minimal hypersurfaces, J. Differential Geom.95(2013), no. 3, 355–388. MR3128988
work page 2013
-
[9]
Giada Franz,Equivariant index bound for min-max free boundary minimal surfaces, Calc. Var. Partial Dif- ferential Equations62(2023), no. 7, Paper No. 201, 28. MR4621518
work page 2023
-
[10]
Mikhail Gromov,Dimension, nonlinear spectra and width, Geometric aspects of functional analysis (1986/87), 1988, pp. 132–184. MR950979
work page 1986
-
[11]
,Isoperimetry of waists and concentration of maps, Geom. Funct. Anal.13(2003), no. 1, 178–215. MR1978494
work page 2003
-
[12]
Qiang Guang, Martin Man-chun Li, Zhichao Wang, and Xin Zhou,Min-max theory for free boundary minimal hypersurfaces II: general Morse index bounds and applications, Math. Ann.379(2021), no. 3-4, 1395–1424. MR4238268
work page 2021
-
[13]
Larry Guth,Minimax problems related to cup powers and Steenrod squares, Geom. Funct. Anal.18(2009), no. 6, 1917–1987. MR2491695
work page 2009
-
[14]
S¨ oren Illman,The equivariant triangulation theorem for actions of compact Lie groups, Math. Ann.262 (1983), no. 4, 487–501. MR696520
work page 1983
-
[15]
Marques, and Andr´ e Neves,Density of minimal hypersurfaces for generic metrics, Ann
Kei Irie, Fernando C. Marques, and Andr´ e Neves,Density of minimal hypersurfaces for generic metrics, Ann. of Math. (2)187(2018), no. 3, 963–972. MR3779962
work page 2018
- [16]
- [17]
-
[18]
Xingzhe Li, Tongrui Wang, and Xuan Yao,Minimal surfaces with low genus in lens spaces, J. Reine Angew. Math.828(2025), 175–218. MR4979239
work page 2025
-
[19]
Xinze Li and Bruno Staffa,On the equidistribution of closed geodesics and geodesic nets, Trans. Amer. Math. Soc.376(2023), no. 12, 8825–8855. MR4669312
work page 2023
-
[20]
Differential Geom.124(2023), no
Yangyang Li,Existence of infinitely many minimal hypersurfaces in higher-dimensional closed manifolds with generic metrics, J. Differential Geom.124(2023), no. 2, 381–395. MR4602728
work page 2023
-
[21]
Marques, and Andr´ e Neves,Weyl law for the volume spectrum, Ann
Yevgeny Liokumovich, Fernando C. Marques, and Andr´ e Neves,Weyl law for the volume spectrum, Ann. of Math. (2)187(2018), no. 3, 933–961. MR3779961 INFINITE EXISTENCE OF EQUIVARIANT MINIMAL HYPERSURFACES 29
work page 2018
-
[22]
Zhenhua Liu,The existence of embeddedG-invariant minimal hypersurface, Calc. Var. Partial Differential Equations60(2021), no. 1, Paper No. 36, 21. MR4204562
work page 2021
-
[23]
Fernando C. Marques and Andr´ e Neves,Existence of infinitely many minimal hypersurfaces in positive Ricci curvature, Invent. Math.209(2017), no. 2, 577–616. MR3674223
work page 2017
-
[24]
,Morse index of multiplicity one min-max minimal hypersurfaces, Adv. Math.378(2021), Paper No. 107527, 58. MR4191255
work page 2021
-
[25]
Fernando C. Marques, Andr´ e Neves, and Antoine Song,Equidistribution of minimal hypersurfaces for generic metrics, Invent. Math.216(2019), no. 2, 421–443. MR3953507
work page 2019
-
[26]
John Douglas Moore and Roger Schlafly,On equivariant isometric embeddings, Math. Z.173(1980), no. 2, 119–133. MR583381
work page 1980
-
[27]
Pitts,Existence and regularity of minimal surfaces on Riemannian manifolds, Mathematical Notes, vol
Jon T. Pitts,Existence and regularity of minimal surfaces on Riemannian manifolds, Mathematical Notes, vol. 27, Princeton University Press, Princeton, NJ; University of Tokyo Press, Tokyo, 1981. MR626027
work page 1981
-
[28]
Jon T Pitts and J Hyam Rubinstein,Applications of minimax to minimal surfaces and the topology of 3- manifolds, Miniconference on geometry/partial differential equations, 2, 1987, pp. 137–171
work page 1987
-
[29]
,Equivariant minimax and minimal surfaces in geometric three-manifolds, Bulletin (New Series) of the American Mathematical Society19(1988), no. 1, 303–309
work page 1988
- [30]
-
[31]
Leon Simon,Lectures on geometric measure theory, The Australian National University, Mathematical Sci- ences Institute, Centre for Mathematics & its Applications, 1983
work page 1983
-
[32]
Francis R Smith,On the existence of embedded minimal2-spheres in the3-sphere, endowed with an arbitrary Riemannian metric, Ph.D. thesis (1982)
work page 1982
-
[33]
Antoine Song,A dichotomy for minimal hypersurfaces in manifolds thick at infinity, Ann. Sci. ´Ec. Norm. Sup´ er. (4)56(2023), no. 4, 1085–1134. MR4650156
work page 2023
-
[34]
,Existence of infinitely many minimal hypersurfaces in closed manifolds, Ann. of Math. (2)197 (2023), no. 3, 859–895. MR4564260
work page 2023
-
[35]
Antoine Song and Xin Zhou,Generic scarring for minimal hypersurfaces along stable hypersurfaces, Geom. Funct. Anal.31(2021), no. 4, 948–980. MR4317508
work page 2021
-
[36]
James Stevens and Ao Sun,Existence of minimal hypersurfaces with arbitrarily large area and possible ob- structions, J. Funct. Anal.287(2024), no. 6, Paper No. 110526, 40. MR4755022
work page 2024
-
[37]
Ren´ e Thom,Quelques propri´ et´ es globales des vari´ et´ es diff´ erentiables, Comment. Math. Helv.28(1954), 17–86. MR61823
work page 1954
-
[38]
Andrei Verona,Triangulation of stratified fibre bundles, Manuscripta Math.30(1979/80), no. 4, 425–445. MR567218
work page 1979
-
[39]
C. T. C. Wall,Differential topology, Cambridge Studies in Advanced Mathematics, vol. 156, Cambridge University Press, Cambridge, 2016. MR3558600
work page 2016
-
[40]
Tongrui Wang,Min-max theory forG-invariant minimal hypersurfaces, J. Geom. Anal.32(2022), no. 9, Paper No. 233, 53. MR4452896
work page 2022
-
[41]
,Min-max theory for free boundaryG-invariant minimal hypersurfaces, Adv. Math.425(2023), Paper No. 109087, 58. MR4587905
work page 2023
-
[42]
,Equivariant min-max hypersurface in G-manifolds with positive Ricci curvature, Pacific J. Math. 331(2024), no. 1, 149–185. MR4810110
work page 2024
-
[43]
,Equivariant Morse index of min-maxG-invariant minimal hypersurfaces, Math. Ann.389(2024), no. 2, 1599–1637. MR4745747
work page 2024
-
[44]
,Generic density of equivariant min-max hypersurfaces, J. Funct. Anal.289(2025), no. 5, Paper No. 110979, 39. MR4890781
work page 2025
- [45]
- [46]
-
[47]
Differential Geom.126 (2024), no
Zhichao Wang,Existence of infinitely many free boundary minimal hypersurfaces, J. Differential Geom.126 (2024), no. 1, 363–399. MR4704552
work page 2024
- [48]
-
[49]
Wasserman,Equivariant differential topology, Topology8(1969), 127–150
Arthur G. Wasserman,Equivariant differential topology, Topology8(1969), 127–150. MR250324 30 XINGZHE LI AND TONGRUI WANG
work page 1969
-
[50]
Brian White,Currents and flat chains associated to varifolds, with an application to mean curvature flow, Duke Math. J.148(2009), no. 1, 41–62. MR2515099
work page 2009
-
[51]
,The maximum principle for minimal varieties of arbitrary codimension, Comm. Anal. Geom.18 (2010), no. 3, 421–432. MR2747434
work page 2010
-
[52]
Shing Tung Yau,Problem section, Seminar on Differential Geometry, 1982, pp. 669–706. MR645762
work page 1982
-
[53]
Xin Zhou,Min-max minimal hypersurface in(M n+1, g)withRic >0and2≤n≤6, J. Differential Geom. 100(2015), no. 1, 129–160. MR3326576
work page 2015
-
[54]
,On the multiplicity one conjecture in min-max theory, Ann. of Math. (2)192(2020), no. 3, 767–820. MR4172621 Cornell University, Department of Mathematics, Ithaca, New York 14850 Email address:xl833@cornell.edu School of Mathematical Sciences, Shanghai Jiao Tong University, 800 Dongchuan RD, Minhang District, Shanghai, 200240, China Email address:wangtong...
work page 2020
discussion (0)
Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.