×

Finite time blowup of the \(n\)-harmonic flow on \(n\)-manifolds. (English) Zbl 1390.58010

Let \(M^n\) be an \(n\)-dimensional Riemannian manifold without boundary, and let \(N^m\) be another \(m\)-dimensional compact Riemannian manifold without boundary (isometrically embedded into \({\mathbb R}^L\)). For a map \(u : M \to N \hookrightarrow {\mathbb R}^L\), the \(n\)-energy functional of \(u\) is defined by \[ E_n(u) = \frac{1}{n}\int_M |\nabla u|^2\, dv. \] A \(C^1\)-map \(u\) from \(M\) to \(N\) is said to be an \(n\)-harmonic map if \(u\) is a critical point of the \(n\)-energy functional, i.e., it satisfies \[ \frac{1}{\sqrt{|g|}}\frac{\partial}{\partial x^i}\left[|\nabla u|^{n-2}g^{ij}\sqrt{|g|} \frac{\partial}{\partial x^j}u\right] + |\nabla u|^{n-2}A(u)(\nabla u, \nabla u) =0, \] where \(A\) is the second fundamental form of \(N\).
In this paper, the authors consider the \(n\)-harmonic map flow in the following setting: \[ \frac{\partial u}{\partial t} = \frac{1}{\sqrt{|g|}}\frac{\partial}{\partial x^i}\left[|\nabla u|^{n-2}g^{ij}\sqrt{|g|} \frac{\partial}{\partial x^j}u\right] + |\nabla u|^{n-2}A(u)(\nabla u, \nabla u). \] N. Hungerbühler [Ann. Sc. Norm. Super. Pisa, Cl. Sci., IV. Ser. 24, No. 4, 593–631 (1997; Zbl 0911.58011)] proved that there exists a global weak solution \(u : M\times [0, \infty) \to N\) of the \(n\)-harmonic map flow with initial value \(u_0\) such that \(u_0\in C^{1, \alpha}(M \times (0, \infty)\setminus \{\Sigma_k \times T_k\}_{k=1}^m)\)for a finite number of times \(\{T_k\}\) and a finite number of singular closed sets \(\Sigma_k \subset M\). Based on the fundamental result of K.-C. Chang et al. [J. Differ. Geom. 36, No. 2, 507–515 (1992; Zbl 0765.53026)] for \(n=2\) and supported by some numerical evidences, Hungerbühler also conjectured the phenomenon of finite time blowup of the \(n\)-harmonic flow for \(n \geq 3\).
In this paper, the authors generalize the no-neck result of J. Qing and G. Tian [Commun. Pure Appl. Math. 50, No. 4, 295–310 (1997; Zbl 0879.58017)] to the \(n\)-harmonic map flow, and as an application of this generalized no-neck result, they settle the conjecture proposed by Hungerbühler by constructing an example to show that the \(n\)-harmonic map flow on an \(n\)-dimensional Riemannian manifold blows up in finite time for \(n \geq 3\).

MSC:

58E20 Harmonic maps, etc.
53C43 Differential geometric aspects of harmonic maps

References:

[1] Chang, K.C., Ding, W.Y., Ye, R.: Finite-time blow-up of the heat flow of harmonic maps from surfaces. J. Differ. Geom. 36, 507-515 (1992) · Zbl 0765.53026 · doi:10.4310/jdg/1214448751
[2] Chen, C.-N., Cheung, L.F., Choi, Y.S., Law, C.K.: On the blow-up of heat flow for conformal \[33\]-harmonic maps. Trans. Am. Math. Soc. 354, 5087-5110 (2002) · Zbl 1112.58303 · doi:10.1090/S0002-9947-02-03054-4
[3] Chen, J., Li, Y.: Homotopy classes of harmonic maps of the stratified \[22\]-spheres and applications to geometric flows. Adv. Math. 263, 357-388 (2014) · Zbl 1303.58005 · doi:10.1016/j.aim.2014.07.001
[4] Coron, J.-M., Ghidaglia, J.-M.: Explosion en temps fini pour le flot des applications harmoniques. C. R. Acad. Sci. Paris Sér. I Math. 308, 339-344 (1989) · Zbl 0679.58017
[5] DiBenedetto, E., Friedman, A.: Holder estimates for nonlinear degenerate parabolic systems. J. Reine Angew. Math. 357, 1-22 (1985) · Zbl 0549.35061
[6] Ding, W., Tian, G.: Energy identity for a class of approximate harmonic maps from surfaces. Comm. Anal. Geom. 3, 543-554 (1995) · Zbl 0855.58016 · doi:10.4310/CAG.1995.v3.n4.a1
[7] Duzaar, F., Fuchs, M.: On removable singularities of p-harmonic maps. Annales de l’IHP Analyse non linaire. 5, 543-554 (1995) · Zbl 0715.49040
[8] Eells, J., Lemaire, L.: A report on harmonic maps. Bull. Lond. Math. Soc. 10(1), 1-68 (1978) · Zbl 0401.58003 · doi:10.1112/blms/10.1.1
[9] Eells, J., Sampson, J.H.: Harmonic mappings of Riemannian manifolds. Am. J. Math. 86, 109-160 (1964) · Zbl 0122.40102 · doi:10.2307/2373037
[10] Gilbarg, D., Trudinger, N.: Elliptic partial differential equations of second order, 2nd edn. Springer, Berlin (1983) · Zbl 0562.35001 · doi:10.1007/978-3-642-61798-0
[11] Hamilton, R.: Harmonic maps of manifolds with boundary. Lecture Notes in Mathematics, vol. 471. Springer, Berlin (1975) · Zbl 0308.35003
[12] Hélein, F.: Régularité des applications faiblement harmoniques entre une surface et une variété riemannienne. C. R. Acad. Sci. Paris Sér. I Math. 312(8), 591-596 (1991) · Zbl 0728.35015
[13] Hong, M.-C.: The rectified n-harmonic map flow with applications to homotopy classes. Ann. Scuola Norm. Sup. Pisa Cl. Sci. (To appear) · Zbl 1404.53079
[14] Hong, M.-C., Hsi, D.: The heat flow for \[HH\]-systems on higher dimensional manifolds. Indiana Univ. Math. J. 59, 761-790 (2010) · Zbl 1210.53065 · doi:10.1512/iumj.2010.59.3917
[15] Hong, M.-C., Yin, H.: On the Sacks-Uhlenbeck flow of Riemannian surfaces. Commun. Anal. Geom. 21, 917-955 (2013) · Zbl 1288.53060 · doi:10.4310/CAG.2013.v21.n5.a3
[16] Hungerbühler, \[N.: p\] p-harmonic flow, PhD thesis, ETH Zürich, Diss. Math. Wiss (1994) · Zbl 1112.58303
[17] Hungerbühler, \[N.: m\] m-harmonic flow, Ann. Scuola Norm. Sup. Pisa Cl. Sci. (4) XXIV, 4, 593-631 (1997) · Zbl 0911.58011
[18] Jost, J.: Harmonic maps between surfaces. Springer, Berlin (1984) · Zbl 0542.58002
[19] Li, J., Zhu, X.: Energy identity for the maps from a surface with tension field bounded in \[L^p\] Lp. Pac. J. Math. 260-1, 181-195 (2012) · Zbl 1270.58011 · doi:10.2140/pjm.2012.260.181
[20] Liu, L., Yin, H.: On the finite time below-up of biharmonic map flow in dimension four. J. Elliptic Parabol. Equ. 1, 363-385 (2015) · Zbl 1415.58010 · doi:10.1007/BF03377386
[21] Liu, L., Yin, H.: Neck analysis for biharmonic maps. Math. Z. 283(3-4), 807-834 (2016) · Zbl 1355.58004 · doi:10.1007/s00209-016-1622-0
[22] Parker, T.: Bubble tree convergence for harmonic maps. J. Differ. Geom. 44, 595-633 (1996) · Zbl 0874.58012 · doi:10.4310/jdg/1214459224
[23] Qing, J.: On singularities of the heat flow for harmonic maps from surfaces into spheres. Commun. Anal. Geom. 3(1-2), 297-315 (1995) · Zbl 0868.58021 · doi:10.4310/CAG.1995.v3.n2.a4
[24] Qing, J., Tian, G.: Bubbling of the heat flows for harmonic maps from surfaces. Commun. Pure Appl. Math. 50, 295-310 (1997) · Zbl 0879.58017 · doi:10.1002/(SICI)1097-0312(199704)50:4<295::AID-CPA1>3.0.CO;2-5
[25] Sacks, J., Uhlenbeck, K.: The existence of minimal immersions of \[22\]-spheres. Ann. Math. 113, 1-24 (1981) · Zbl 0462.58014 · doi:10.2307/1971131
[26] Struwe, M.: On the evolution of harmonic maps of Riemannian surfaces. Commun. Math. Helv. 60, 558-581 (1985) · Zbl 0595.58013 · doi:10.1007/BF02567432
[27] Wang, C., Wei, S.: Energy identity for \[m\] m-harmonic maps. Differ. Integr. Equ. 15, 1519-1532 (2002) · Zbl 1037.58011
This reference list is based on information provided by the publisher or from digital mathematics libraries. Its items are heuristically matched to zbMATH identifiers and may contain data conversion errors. In some cases that data have been complemented/enhanced by data from zbMATH Open. This attempts to reflect the references listed in the original paper as accurately as possible without claiming completeness or a perfect matching.