On Irreducible Four–manifolds
نویسنده
چکیده
For many years, four–manifold folklore suggested that all simply connected smooth four–manifolds should be connected sums of complex algebraic surfaces, with both their complex and non–complex orientations allowed. The first counterexamples were constructed in 1990 by Gompf and Mrowka [5], and many others followed. Then, Gompf [4] showed that many, and possibly all, these counterexamples arise from symplectic four–manifolds. Having no indication to the contrary, many people have put forward the following:
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