## Slopes of vector bundles on projective curves and applications to tight closure problems

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- by Holger Brenner
- Trans. Amer. Math. Soc.
**356**(2004), 371-392 - DOI: https://doi.org/10.1090/S0002-9947-03-03391-9
- Published electronically: August 25, 2003
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## Abstract:

We study different notions of slope of a vector bundle over a smooth projective curve with respect to ampleness and affineness in order to apply this to tight closure problems. This method gives new degree estimates from above and from below for the tight closure of a homogeneous $R_+$-primary ideal in a two-dimensional normal standard-graded algebra $R$ in terms of the minimal and the maximal slope of the sheaf of relations for some ideal generators. If moreover this sheaf of relations is semistable, then both degree estimates coincide and we get a vanishing type theorem.## References

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## Bibliographic Information

**Holger Brenner**- Affiliation: Mathematische Fakultät, Ruhr-Universität Bochum, 44780 Bochum, Germany
- MR Author ID: 322383
- Email: Holger.Brenner@ruhr-uni-bochum.de
- Received by editor(s): May 21, 2002
- Received by editor(s) in revised form: February 19, 2003
- Published electronically: August 25, 2003
- © Copyright 2003 American Mathematical Society
- Journal: Trans. Amer. Math. Soc.
**356**(2004), 371-392 - MSC (2000): Primary 13A35, 14H60
- DOI: https://doi.org/10.1090/S0002-9947-03-03391-9
- MathSciNet review: 2020037