ISSN : 1226-0657
We present a 4-dimensional nil-manifold as the first example of a closed non-K<TEX>$\ddot{a}$</TEX>hlerian symplectic manifold with the following property: a function is the scalar curvature of some almost K<TEX>$\ddot{a}$</TEX>hler metric iff it is negative somewhere. This is motivated by the Kazdan-Warner's work on classifying smooth closed manifolds according to the possible scalar curvature functions.
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