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The Calabi-Yau equation on almost-Kahler four-manifolds

Ben Weinkove
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Abstract

Let (M, ω) be a compact symplectic 4-manifold with a compatible almost complex structure J. The problem of finding a J-compatible symplectic form with prescribed volume form is an almost-Kähler analogue of Yau's theorem and is connected to a programme in symplectic topology proposed by Donaldson. We call the corresponding equation for the symplectic form the Calabi-Yau equation. Solutions are unique in their cohomology class. It is shown in this paper that a solution to this equation exists if the Nijenhuis tensor is small in a certain sense. Without this assumption, it is shown that the problem of existence can be reduced to obtaining a C^0 bound on a scalar potential function.

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Ben Weinkove. 2007-03-26. The Calabi-Yau equation on almost-Kahler four-manifolds. https://arxiv.org/abs/math/0604408

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