Kronheimer–Mrowka basic class

In mathematics, the Kronheimer–Mrowka basic classes are elements of the second cohomology H 2 ( M ; Z ) {\displaystyle H^{2}(M;\mathbb {Z} )} of a simply connected, smooth 4-manifold M {\displaystyle M} of simple type that determine its Donaldson polynomials. They were introduced by Peter B. Kronheimer and Tomasz S. Mrowka (1994, 1995).

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