= Gompf realization theorem
{c}
Every finitely presented group is the <fundamental group> of a closed symplectic four-manifold. The construction starts from products of surfaces, realizes relator words by embedded loops after stabilization, and takes <symplectic sums> with copies of the <rational elliptic surface> along square-zero tori. Since the complement of a regular elliptic fiber in the rational elliptic surface is simply connected, van Kampen's theorem imposes the desired generators and relators.
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