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Harmonic maps and biharmonic Riemannian submersions. (English) Zbl 1432.58012

Biharmonic maps are critical points of the functional \[ E_2(\phi) = \int_M |\tau(\phi)|^2 \, v_g \] where \(\tau(\phi)\) is the tension field of \(\phi\), and generalise harmonic maps.
This article studies the biharmonicity of the projection \(\pi : (P,g) \to (M,h)\) where \((P,g)\) is an \({\mathbb S}^1\)-bundle over a compact Riemannian manifold \((M,h)\) and \(\pi\) is a Riemannian submersion.
First, it is proved that for a base manifold with non-positive Ricci curvature, when \(\pi\) is biharmonic, if the tension field of \(\pi\) is divergence-free then it must be parallel.
The cases of a weakly stable Einstein base manifold and of an irreducible compact Hermitian symmetric space are studied in more details and characterisations of the biharmonicity of the bundle projection are given.
This article closes with explicit examples of Kähler-Einstein flag manifolds \(K/T\) with an \({\mathbb S}^1\)-bundle such that the projection is biharmonic but not harmonic.

MSC:

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

References:

[1] K. Akutagawa and S. Maeta: Complete biharmonic submanifolds in the Euclidean spaces, Geometriae Dedicata, 164 (2013), 351-355. · Zbl 1268.53068
[2] M.A. Akyol and Y.L. Ou: Biharmonic Riemannian submersions, 2018, arXiv: 1805.04754v1. · Zbl 1411.58006
[3] P. Paird and D. Kamissoko: On constructing biharmonic maps and metrics, Ann. Global Anal. Geom. 23 (2003), 65-75. · Zbl 1027.31004
[4] P. Baird and J.C. Wood: Harmonic morphisms between Riemannian manifolds, London Math. Soc. Monographs, Oxford, 2003. · Zbl 1055.53049
[5] A. Balmus, S. Montaldo and C. Oniciuc: Classification results for biharmonic submanifolds in spheres, Israel J. Math., 168 (2008), 201-220. · Zbl 1172.58004
[6] A. Balmus, S. Montaldo and C. Oniciuc: Biharmonic hypersurfaces in 4-dimensional space forms, Math. Nachr., 283 (2010), 1696-1705. · Zbl 1210.58013
[7] C. Boyer and K. Galicki: Sasakian Geometry, Oxford Sci. Publ., 2008. · Zbl 1155.53002
[8] R. Caddeo, S. Montaldo, P. Piu: On biharmonic maps, Contemp. Math., 288 (2001), 286-290. · Zbl 1010.58009
[9] I. Castro, H.Z. Li and F. Urbano: Hamiltonian-minimal Lagrangian submanifolds in complex space forms, Pacific J. Math., 227 (2006), 43-63. · Zbl 1129.53039
[10] B.Y. Chen: Some open problems and conjectures on submanifolds of finite type, Soochow J. Math., 17 (1991), 169-188. · Zbl 0749.53037
[11] F. Defever: Hypersurfaces in E5with harmonic mean curvature vector, Math. Nachr., 196 (1998), 61-69. · Zbl 0944.53005
[12] J. Eells and L. Lemaire: Selected Topics in Harmonic Maps, CBMS, Regional Conference Series in Math., Amer. Math. Soc., 50, 1983. · Zbl 0515.58011
[13] D. Fetcu and C. Oniciuc: Biharmonic integral C-parallel submanifolds in 7-dimensional Sasakian space forms, Tohoku Math. J., 64 (2012), 195-222. · Zbl 1258.53059
[14] T. Hasanis and T. Vlachos: Hypersurfaces in E4with harmonic mean curvature vector field, Math. Nachr., 172 (1995), 145-169. · Zbl 0839.53007
[15] T. Ichiyama, J. Inoguchi, H. Urakawa: Biharmonic maps and bi-Yang-Mills fields, Note di Mat., 28, (2009), 233-275. · Zbl 1201.58012
[16] T. Ichiyama, J. Inoguchi, H. Urakawa: Classifications and isolation phenomena of biharmonic maps and bi-Yang-Mills fields, Note di Mat., 30, (2010), 15-48. · Zbl 1244.58006
[17] J. Inoguchi: Submanifolds with harmonic mean curvature vector filed in contact 3manifolds, Colloq. Math., 100 (2004), 163-179. · Zbl 1076.53065
[18] H. Iriyeh: Hamiltonian minimal Lagrangian cones in Cm, Tokyo J. Math., 28 (2005), 91-107. · Zbl 1087.53057
[19] S. Ishihara and S. Ishikawa: Notes on relatively harmonic immersions, Hokkaido Math. J., 4 (1975), 234-246. · Zbl 0311.53063
[20] G.Y. Jiang: 2-harmonic maps and their first and second variational formula, Chinese Ann. Math., 7A (1986), 388-402; Note di Mat., 28 (2009), 209-232. · Zbl 1200.58015
[21] T. Kajigaya: Second variation formula and the stability of Legendrian minimal submanifolds in Sasakian manifolds, Tohoku Math. J., 65 (2013), 523-543. · Zbl 1287.53054
[22] S. Kobayashi: Transformation Groups in Differential Geometry, Springer, 1972. · Zbl 0246.53031
[23] E. Loubeau, C. Oniciuc: The index of biharmonic maps in spheres, Compositio Math., 141 (2005), 729-745. · Zbl 1075.58014
[24] E. Loubeau and C. Oniciuc: On the biharmonic and harmonic indices of the Hopf map, Trans. Amer. Math. Soc., 359 (2007), 5239-5256. · Zbl 1124.58009
[25] E. Loubeau and Y-L. Ou: Biharmonic maps and morphisms from conformal mappings, Tohoku Math. J., 62 (2010), 55-73. · Zbl 1202.53061
[26] S. Maeta and U. Urakawa: Biharmonic Lagrangian submanifolds in K¨ahler manifolds, Glasgow Math. J. , 55 (2013), 465-480. · Zbl 1281.58009
[27] S. Montaldo, C. Oniciuc: A short survey on biharmonic maps between Riemannian manifolds, Rev. Un. Mat. Argentina 47 (2006), 1-22. · Zbl 1140.58004
[28] Y. Nagatomo: Harmonic maps into Grassmannians and a generalization of do CarmoWallach theorem, Proc. the 16th OCU Intern. Academic Symp. 2008, OCAMI Studies, 3 (2008), 41-52. · Zbl 1254.58007
[29] N. Nakauchi and H. Urakawa : Biharmonic hypersurfaces in a Riemannian manifold with non-positive Ricci curvature, Ann. Global Anal. Geom., 40 (2011), 125-131. · Zbl 1222.58010
[30] N. Nakauchi and H. Urakawa: Biharmonic submanifolds in a Riemannian manifold with non-positive curvature, Results in Math.,63 (2013), 467-474. · Zbl 1261.58011
[31] N. Nakauchi, H. Urakawa and S. Gudmundsson: Biharmonic maps into a Riemannian manifold of non-positive curvature, Geom. Dedicata, 169. (2014), 263-272. · Zbl 1316.58012
[32] C. Oniciuc: Biharmonic maps between Riemannian manifolds, Ann. Stiint Univ. A‘. I. Cuza Iasi, Mat. (N.S.), 48 No. 2, (2002), 237-248. · Zbl 1061.58015
[33] B. O’Neill: The fundamental equation of a submersion, Michigan Math. J., 13 (1966), 459-469. · Zbl 0145.18602
[34] S. Ohno, T. Sakai and H. Urakawa: Biharmonic homogeneous hypersurfaces in compact symmetric spaces, Differ. Geom. Appl., 43 (2015), 155-179. · Zbl 1336.58009
[35] S. Ohno, T. Sakai and H. Urakawa: Rigidity of transversally biharmonic maps between foliated Riemannian manifolds, to appear in Hokkaido Math. J. · Zbl 1408.58013
[36] Ye-Lin Ou and Liang Tang: The generalized Chen’s conjecture on biharmonic submanifolds is false, arXiv: 1006.1838v1. · Zbl 1268.58015
[37] Ye-Lin Ou and Liang Tang: On the generalized Chen’s conjecture on biharmonic submanifolds, Michigan Math. J., 61 (2012), 531-542. · Zbl 1268.58015
[38] T. Sasahara: Legendre surfaces in Sasakian space forms whose mean curvature vectors are eigenvectors, Publ. Math. Debrecen, 67 (2005), 285-303. · Zbl 1082.53067
[39] T. Sasahara: Stability of biharmonic Legendrian submanifolds in Sasakian space forms, Canad. Math. Bull. 51 (2008), 448-459. · Zbl 1147.53315
[40] T. Sasahara: A class of biminimal Legendrian submanifolds in Sasaki space forms, a preprint, 2013, to appear in Math. Nach.
[41] T. Takahashi: Minimal immersions of Riemannian manifoplds, J. Math. Soc. Japan, 18 (1966), 380-385. · Zbl 0145.18601
[42] M. Takeuchi and S. Kobayashi: Minimal imbeddings of R-space, J. Differ. Geom., 2 (1968), 203-213. · Zbl 0165.24901
[43] H. Urakawa: The first eigenvalue of the Laplacian for a positively curved homogeneous Riemannian manifold, Compositio Math., 59 (1986), 57-71. · Zbl 0615.53040
[44] H. Urakawa: CR rigidity of pseudo harmonic maps and pseudo biharmonic maps, Hokkaido Math. J., 46 (2017), 141-187. · Zbl 1376.32036
[45] H. Urakawa: Harmonic maps and biharmonic maps on principal bundles and warped products, J. Korean Math. Soc. 55 (2018), 55, 553-574. · Zbl 1414.58012
[46] H. Urakawa: Calculus of Variations and Harmonic Maps, Vol. 132, Amer. Math. Soc., 1990.
[47] Z-P Wang and Y-L Ou: Biharmonic Riemannian submersions from 3-manifolds, Math. Z., 269 (2011), 917-925. · Zbl 1235.53065
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