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arXiv · 2609.37610

Schreyer Resolutions over the Exterior Algebra

Janko Boehm·Lakshmi Ramesh
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Abstract

Schreyer's algorithm is usually the fastest way to determine a (typically non-minimal) free resolution of a finitely presented module over a polynomial ring. We adapt a refined version of Schreyer's algorithm to compute free resolutions over the exterior algebra, relying on relative Groebner bases. We illustrate the use of our algorithm for the computation of cohomology of coherent sheaves over projective space, which by the BGG correspondence can be computed via free resolutions over the exterior algebra. Schreyer's method relies on a tree traversal and thus has the potential for parallel computations. We report on ongoing work on a massively parallel implementation, observing that Gnawali's parallel approach over polynomial rings can be carried over to our setting.

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Janko Boehm, Lakshmi Ramesh. 2026-09-29. Schreyer Resolutions over the Exterior Algebra. https://arxiv.org/abs/2609.37610

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