# Circle actions on almost complex manifolds with 4 fixed points

@article{Jang2017CircleAO, title={Circle actions on almost complex manifolds with 4 fixed points}, author={Donghoon Jang}, journal={Mathematische Zeitschrift}, year={2017}, volume={294}, pages={287-319} }

Let the circle act on a compact almost complex manifold M . In this paper, we classify the fixed point data of the action if there are 4 fixed points and the dimension of the manifold is at most 6. By the fixed point data we mean a collection of the multisets of the weights at the fixed points. First, if $$\dim M=2$$ dim M = 2 , then M is a disjoint union of rotations on two 2-spheres. Second, if $$\dim M=4$$ dim M = 4 , we prove that the action alikes a circle action on a Hirzebruch surface…

## 15 Citations

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