Riv. Mat. Univ. Parma, Vol. 13, No. 2, 2022

Jun Li [a], Tian-Jun Li [b] and Weiwei Wu [c]

The space of tamed almost complex structures on symplectic 4-manifolds via symplectic spheres

Pages: 651-670
Received: 1 February 2022
Accepted in revised form: 18 May 2022
Mathematics Subject Classification: 57R17.
Keywords: Symplectic 4-manifolds, almost complex structure.
Authors address:
[a]: Department of Mathematics, University of Michigan, Ann Arbor, MI
[b]: School of Mathematics, University of Minnesota, Minneapolis, MN
[c]: Department of Mathematics, University of Georgia, Athens, GA

The authors were supported by NSF, and the first-named author is supported by the AMS-Simons travel grant.

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Abstract: In this note, we study a fine decomposition of the space of tamed almost complex structures for symplectic 4 manifolds via symplectic spheres. We also show that every tamed almost complex structure on a rational surface other than \(\mathbb{C} P^2\) is fibred.

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