  In [11], I. M. Gelfand, V. Retakh, and M. Shubin defined the symplectic
sectional curvature of a torsion-free connection preserving a symplectic form.
The present article defines the corresponding notion of constant symplectic
sectional curvature and characterizes this notion in terms of the curvature
tensor of the symplectic connection and its covariant derivatives. Some
relations between various more general conditions on the symplectic sectional
curvature and the geometry of the symplectic connection or that induced on a
symplectic submanifold are explored as well.
