## Relations in the cohomology ring of the moduli space of rank 2 Higgs bundles

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- by Tamás Hausel and Michael Thaddeus
- J. Amer. Math. Soc.
**16**(2003), 303-329 - DOI: https://doi.org/10.1090/S0894-0347-02-00417-4
- Published electronically: December 3, 2002
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## Abstract:

The moduli space of stable bundles of rank $2$ and degree $1$ on a Riemann surface has rational cohomology generated by the so-called universal classes. The work of Baranovsky, King-Newstead, Siebert-Tian and Zagier provided a complete set of relations between these classes, expressed in terms of a recursion in the genus. This paper accomplishes the same thing for the noncompact moduli spaces of Higgs bundles, in the sense of Hitchin and Simpson. There are many more independent relations than for stable bundles, but in a sense the answer is simpler, since the formulas are completely explicit, not recursive. The results of Kirwan on equivariant cohomology for holomorphic circle actions are of key importance.## References

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*EKHAD*, available from http://www.math.temple.edu/~zeilberg/programs.html/.

*Macaulay 2*, available from http://www.math.uiuc.edu/Macaulay2/.

## Bibliographic Information

**Tamás Hausel**- Affiliation: Department of Mathematics, University of California, Berkeley, California 94720
- Address at time of publication: Department of Mathematics, University of Texas, RLM 11.168, 26th and Speedway, Austin, Texas 78712
- Email: hausel@math.utexas.edu
**Michael Thaddeus**- Affiliation: Department of Mathematics, Columbia University, 2990 Broadway, New York, New York 10027
- Email: thaddeus@math.columbia.edu
- Received by editor(s): June 10, 2002
- Published electronically: December 3, 2002
- Additional Notes: The first author was supported by NSF grant DMS–97–29992

The second author was supported by NSF grant DMS–98–08529 - © Copyright 2002 American Mathematical Society
- Journal: J. Amer. Math. Soc.
**16**(2003), 303-329 - MSC (2000): Primary 14H60; Secondary 14D20, 14H81, 32Q55, 58D27
- DOI: https://doi.org/10.1090/S0894-0347-02-00417-4
- MathSciNet review: 1949162