## Minimizing Euler characteristics of symplectic four-manifolds

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**134**(2006), 3081-3083 Request permission

## Abstract:

We prove that the minimal Euler characteristic of a closed symplectic four-manifold with given fundamental group is often much larger than the minimal Euler characteristic of almost complex closed four-manifolds with the same fundamental group. In fact, the difference between the two is arbitrarily large for certain groups.## References

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## Additional Information

**D. Kotschick**- Affiliation: Mathematisches Institut, Ludwig-Maximilians-Universität München, Theresien- strasse 39, 80333 München, Germany
- MR Author ID: 267229
- Email: dieter@member.ams.org
- Received by editor(s): May 3, 2005
- Published electronically: May 4, 2006
- Additional Notes: The author is grateful to P. Kirk for pointing out the question that is answered here.
- Communicated by: Ronald A. Fintushel
- © Copyright 2006 American Mathematical Society
- Journal: Proc. Amer. Math. Soc.
**134**(2006), 3081-3083 - MSC (2000): Primary 57M07, 57R17, 57R57
- DOI: https://doi.org/10.1090/S0002-9939-06-08352-3
- MathSciNet review: 2231635