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arXiv · 1201.2333

On bundles of rank 3 computing Clifford indices

H. Lange·P. E. Newstead
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Abstract

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 semistable bundles of any rank. Recent work has been focussed 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 non-trivial cases and examples for which the rank-3 index is greater than the rank-2 index.

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H. Lange, P. E. Newstead. 2012-01-11. On bundles of rank 3 computing Clifford indices. https://doi.org/10.1215/21562261-1966062

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