Structures de Hodge mixtes sur les idéaux de saut de cohomologie

Autor: Lefèvre, Louis-Clément
Přispěvatelé: Universität Duisburg-Essen [Essen], ANR-16-CE40-0011,Hodgefun,Groupes fondamentaux, Théorie de Hodge et Motifs(2016)
Jazyk: angličtina
Rok vydání: 2021
Předmět:
Popis: In previous work, we constructed for a smooth complex variety $X$ and for a linear algebraic group $G$ a mixed Hodge structure on the complete local ring $\widehat{\mathcal{O}}_\rho$ to the moduli space of representations of the fundamental group $\pi_1(X,x)$ into $G$ at a representation $\rho$ underlying a variation of mixed Hodge structure. We now show that the jump ideals $J_k^i \subset \widehat{\mathcal{O}}_\rho$, defining the locus of representations such the the dimension of the cohomology of $X$ in degree $i$ of the associated local system is greater than $k$, are sub-mixed Hodge structures; this is in accordance with various known motivicity results for these loci. In rank one we also recover, and find new cases, where these loci are translated sub-tori of the moduli of representations. Our methods are first transcendental, relying on Hodge theory, and then combined with tools of homotopy and algebra.
Comment: 18 pages, comments are welcome!
Databáze: OpenAIRE