In any 5-dimensional closed Sasakian manifold, we prove that any minmax operation on the area among Legendrian surfaces is achieved by a continuous conformal Legendrian map from a closed Riemann surface S into $N^5$ equipped with an integer multiplicity bounded in $L^\infty $. Moreover this map, equipped with this multiplicity, satisfies a weak version of the Hamiltonian Minimal Equation. We conjecture that any solution to this equation is a smooth branched Legendrian immersion away from isolated Schoen–Wolfson conical singularities with non-zero Maslov class.
| [1] |
Allard, W.K.: A characterization of the area integrand. In: Symposia Mathematica, Vol. XIV (Convegno di Geometria Simplettica e Fisica Matematica & Convegno di Teoria Geometrica dell’Integrazione e Varietà Minimali, INDAM, Rome, 1973), pp. 429–444. Academic Press, London (1974)
|
| [2] |
Almeida L. The regularity problem for generalized harmonic maps into homogeneous spaces. Calc. Var. Partial Differ. Equ., 1995, 3(2): 193-242
|
| [3] |
Alvarado, R., Mitrea, M.: Hardy Spaces on Ahlfors-Regular Quasi Metric Spaces—A Sharp Theory. Lecture Notes in Mathematics, vol. 2142. Springer, Cham (2015)
|
| [4] |
Boyer CP, Galicki K. On Sasakian–Einstein geometry. Int. J. Math., 2000, 11(7): 873-909
|
| [5] |
Boyer CP, Galicki K. Sasakian Geometry. Oxford Mathematical Monographs, 2008, Oxford, Oxford University Press
|
| [6] |
Dazord, P.: Sur la géométrie des sous-fibrés et des feuilletages lagrangiens. Ann. Sci. École Norm. Sup. (4) 14(4), 465–480 (1981)
|
| [7] |
Evans LC, Gariepy RF. Measure Theory and Fine Properties of Functions. Studies in Advanced Mathematics, 1992, Boca Raton, CRC Press
|
| [8] |
Godliński M, Kopczyński W, Nurowski P. Locally Sasakian manifolds. Class. Quant. Grav., 2000, 17(18): L105-L115
|
| [9] |
Guan, P., Zhang, X.: A geodesic equation in the space of Sasakian metrics. In: Geometry and Analysis, No. 1, pp. 303–318, Adv. Lect. Math. (ALM), vol. 17. International Press, Somerville (2011)
|
| [10] |
Harvey R, Lawson HBJr. Calibrated geometries. Acta Math., 1982, 148: 47-157
|
| [11] |
Micallef M, Wolfson J. Area minimizers in a K3 surface and holomorphicity. Geom. Funct. Anal., 2006, 16(2): 437-452
|
| [12] |
Oh Y-G. Volume minimization of Lagrangian submanifolds under Hamiltonian deformations. Math. Z., 1993, 212(2): 175-192
|
| [13] |
Oh Y-G. Mean curvature vector and symplectic topology of Lagrangian submanifolds in Einstein–Kähler manifolds. Math. Z., 1994, 216(3): 471-482
|
| [14] |
Pigati A. The viscosity method for min-max free boundary minimal surfaces. Arch. Ration. Mech. Anal., 2022, 244(2): 391-441
|
| [15] |
Pigati A, Rivière T. The regularity of parametrized integer stationary varifolds in two dimensions. Commun. Pure Appl. Math., 2020, 73(9): 1981-2042
|
| [16] |
Rivière, T.: The regularity of conformal target harmonic maps. Calc. Var. Partial Differ. Equ. 56(4), Paper No. 117, 15 pp. (2017)
|
| [17] |
Rivière T. A viscosity method in the min-max theory of minimal surfaces. Publ. Math. Inst. Hautes Études Sci., 2017, 126: 177-246
|
| [18] |
Rivière T. Almost monotonicity formula for H-minimal Legendrian surfaces in the Heisenberg group. Commun. Pure Appl. Math., 2024, 77(3): 1940-1957
|
| [19] |
Schoen, R., Wolfson, J.: Minimizing volume among Lagrangian submanifolds. In: Differential Equations: La Pietra 1996 (Florence), pp. 181–199, Proc. Sympos. Pure Math., vol. 65. Amer. Math. Soc., Providence (1999)
|
| [20] |
Schoen R, Wolfson J. Minimizing area among Lagrangian surfaces: the mapping problem. J. Differ. Geom., 2001, 58(1): 1-86
|
| [21] |
Simon, L.: Lectures on Geometric Measure Theory. Proceedings of the Centre for Mathematical Analysis, Australian National University, vol. 3. Australian National University, Canberra (1983)
|
| [22] |
Sparks, J.: Sasaki–Einstein manifolds. In: Surveys in Differential Geometry, Volume XVI, Geometry of Special Holonomy and Related Topics, pp. 265–324, Surv. Differ. Geom., vol. 16. Int. Press, Somerville (2011)
|
| [23] |
Vezzoni L, Zedda M. On the J-flow in Sasakian manifolds. Ann. Mat. Pura Appl. (4), 2016, 195(3): 757-774
|
| [24] |
Wolfson JG. Minimal Lagrangian diffeomorphisms and the Monge-Ampère equation. J. Differ. Geom., 1997, 46(2): 335-373
|
| [25] |
Wolfson JG. Lagrangian homology classes without regular minimizers. J. Differ. Geom., 2005, 71(2): 307-313
|
Funding
Swiss Federal Institute of Technology Zurich
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