2018/06/21 by Tim-Henrik Bülles, Bülles, Tim-Henrik · 1 citation
Mathematics · #Advanced Algebra and Geometry #Algebraic Geometry (math.AG) #Algebraic Geometry and Number Theory #Algebraic structures and combinatorial models #FOS: Mathematics
paper · pdf · doi:10.48550/arxiv.1806.08284
openalex publication_date 2018/06/21 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
For any smooth projective moduli space M of Gieseker stable sheaves on a complex projective K3 surface (or an abelian surface) S, we prove that the Chow motive \mathfrakh(M) becomes a direct summand of a motive \bigoplus \mathfrakh(Ski)(ni) with ki≤ dim(M). The result implies that finite dimensionality of \mathfrakh(M) follows from finite dimensionality of \mathfrakh(S). The technique also applies to moduli spaces of twisted sheaves and to moduli spaces of stable objects in \rm D\rm b(S,α) for a Brauer class α∈\rm Br(S). In a similar vein, we investigate the relation between the Chow motives of a K3 surface S and a cubic fourfold X when there exists an isometry \widetilde H(S,α,ℤ) ≃ \widetilde H(\cal AX,ℤ). In this case, we prove that there is an isomorphism of transcendental Chow motives \mathfrakt(S)(1) ≃ \mathfrakt(X).