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arXiv · 1108.2292

On minimal Lefschetz decompositions for Grassmannians

Anton Fonarev
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Abstract

We construct two Lefschetz decompositions of the derived category of coherent sheaves on the Grassmannian of $k$-dimensional subspaces in a vector space of dimension $n$. Both of them admit a Lefschetz basis consisting of equivariant vector bundles. We prove fullness of the first decomposition and conjecture it for the second one. In the case when $n$ and $k$ are coprime these decompositions coincide and are minimal. In general, we conjecture minimality of the second decomposition.

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Anton Fonarev. 2011-08-10. On minimal Lefschetz decompositions for Grassmannians. https://doi.org/10.4213/im7930

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