Journal of the
Korean Mathematical Society JKMS

Main interest of the present paper is to investigate the criticality of characteristic vector fields on almost cosymplectic manifolds. Killing critical characteristic vector fields are absolute minima. This paper contains some examples of non-Killing critical characteristic vector fields.

Keywords: critical unit vector field, harmonic map, $\phi$-holomorphic map, almost cosymplectic manifold, Sasaki metric

MSC numbers: 53C15, 53C20