Article
Keywords:
cosymplectic manifolds; solvmanifolds; Kähler manifolds; suspensions; flat Riemannian manifolds
Summary:
In this paper we present new examples of $(2n+1)$-dimensional compact cosymplectic manifolds which are not topologically equivalent to the canonical examples, i.e., to the pro\-duct of the $(2m+1)$-dimensional real torus and the $r$-dimensional complex projective space, with $m,r\geq 0$ and $m+r=n.$ These new examples are compact solvmanifolds and they are constructed as suspensions with fibre the $2n$-dimensional real torus. In the particular case $n=1,$ using the examples obtained, we conclude that a $3$-dimensional compact flat orientable Riemannian manifold with non-zero first Betti number admits a cosymplectic structure. Furthermore, if the first Betti number is equal to $1$ then such a manifold is not topologically equivalent to the global product of a compact Kähler manifold with the circle $S^1.$
References:
[1] Blair D. E.:
Contact manifolds in Riemannian geometry. Lecture Notes in Math., 509, Springer-Verlag, Berlin, (1976).
MR 0467588 |
Zbl 0319.53026
[2] Blair D. E., Goldberg S. I.:
Topology of almost contact manifolds. J. Diff. Geometry, 1, 347-354 (1967).
MR 0226539 |
Zbl 0163.43902
[3] Chinea D., León M. de, Marrero J. C.:
Topology of cosymplectic manifolds. J. Math. Pures Appl., 72, 567-591 (1993).
MR 1249410 |
Zbl 0845.53025
[4] Hector G., Hirsch U.:
Introduction to the Geometry of Foliations. Part A. Aspects of Math., Friedr. Vieweg and Sohn, (1981).
MR 0639738 |
Zbl 0486.57002
[5] León M. de, Marrero J. C.:
Compact cosymplectic manifolds with transversally positive definite Ricci tensor. Rendiconti di Matematica, Serie VII, 17 Roma, 607-624 (1997).
MR 1620868 |
Zbl 0897.53026
[6] Wolf J. A.:
Spaces of constant curvature. 5nd ed., Publish or Perish, Inc., Wilmington, Delaware, (1984).
MR 0928600 |
Zbl 0556.53033