Kyoto Journal of Mathematics

On bundles of rank 3 computing Clifford indices

H. Lange and P. E. Newstead

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Let C be a smooth irreducible projective algebraic curve defined over the complex numbers. The notion of the Clifford index of C was extended a few years ago to[4] semistable bundles of any rank. Recent work has been focused mainly on the rank-2 Clifford index, although interesting results have also been obtained for the case of rank 3. In this paper we extend this work, obtaining improved lower bounds for the rank-3 Clifford index. This allows the first computations of the rank-3 index in nontrivial cases and examples for which the rank-3 index is greater than the rank-2 index.

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Kyoto J. Math., Volume 53, Number 1 (2013), 25-54.

First available in Project Euclid: 25 March 2013

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Mathematical Reviews number (MathSciNet)

Zentralblatt MATH identifier

Primary: 14H60: Vector bundles on curves and their moduli [See also 14D20, 14F05]
Secondary: 14J28: $K3$ surfaces and Enriques surfaces


Lange, H.; Newstead, P. E. On bundles of rank $3$ computing Clifford indices. Kyoto J. Math. 53 (2013), no. 1, 25--54. doi:10.1215/21562261-1966062.

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