Symplectic Geometry and Rationally Connected 4-folds
نویسنده
چکیده
We study some symplectic geometric aspects of rationally connected 4-folds. As a corollary, we prove that any smooth projective 4-fold symplectic deformation equivalent to a Fano 4-fold of pseudo-index at least 2 or a rationally connected 4-fold whose second Betti number is 2 is rationally connected.
منابع مشابه
Rationally connected 3-folds and symplectic geometry
The first condition tells that ω is of type (1, 1). The last condition is called the taming condition. We will consider more generally taming symplectic forms α on X. These forms are thus non necessarily of type (1, 1) but their (1, 1)-part is positive (but not necessarily closed). Let X and Y be two complex projective or compact Kähler manifolds. The set of taming symplectic forms on X, resp. ...
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