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pro vyhledávání: '"Lazda, Christopher"'
We prove that the transcendental Brauer group of a K3 surface X over a finitely generated field k is finite, unless k has positive characteristic p and X is supersingular, in which case it is annihilated by p.
Comment: 21 pages
Comment: 21 pages
Externí odkaz:
http://arxiv.org/abs/2407.07989
Autor:
Lazda, Christopher
In this article, I define triangulated categories of constructible isocrystals on varieties over a perfect field of positive characteristic, in which Le Stum's abelian category of constructible isocrystals sits as the heart of a natural t-structure.
Externí odkaz:
http://arxiv.org/abs/2304.07181
Autor:
Abe, Tomoyuki, Lazda, Christopher
The goal of this article is to prove a comparison theorem between rigid cohomology and cohomology computed using the theory of arithmetic $\mathscr{D}$-modules. To do this, we construct a specialisation functor from Le Stum's category of constructibl
Externí odkaz:
http://arxiv.org/abs/2208.10137
Publikováno v:
Ãpijournal de Géométrie Algébrique, Volume 7 (March 23, 2023) epiga:9657
We obtain necessary and sufficient conditions for the good reduction of Kummer surfaces attached to abelian surfaces with non-supersingular reduction when the residue field is perfect of characteristic 2. In this case, good reduction with an algebrai
Externí odkaz:
http://arxiv.org/abs/2205.13831
Autor:
Abe, Tomoyuki, Lazda, Christopher
We construct proper pushforwards for partially proper morphisms of analytic adic spaces. This generalises the theory due to van der Put in the case of rigid analytic varieties over a non-Archimedean field. For morphisms which are smooth and partially
Externí odkaz:
http://arxiv.org/abs/2009.05433
Publikováno v:
Ann. Sc. Norm. Super. Pisa Cl. Sci. (5) 23 (2022), no. 1, 483-500
We show that for smooth and proper varieties over local fields with no non-trivial vector fields, good reduction descends over purely inseparable extensions. We use this to extend the Neron-Ogg-Shafarevich criterion for K3 surfaces to the equicharact
Externí odkaz:
http://arxiv.org/abs/1902.02630
Publikováno v:
Journal of Algebra, Volume 527, 2019, Pages 348-365, ISSN 0021-8693
We construct the (filtered) Ogus realisation of Voevodsky motives over a number field $K$. This realisation extends the functor defined on $1$-motives by Andreatta, Barbieri-Viale and Bertapelle. As an illustration we note that the analogue of the Ta
Externí odkaz:
http://arxiv.org/abs/1808.03146
Autor:
Lazda, Christopher
We prove an analogue for $p$-adic coefficients of the Deligne--Laumon theorem on local acyclicity for curves. That is, for an overconvergent $F$-isocrystal $E$ on a relative curve $f:U\rightarrow S$ admitting a good compactification, we show that the
Externí odkaz:
http://arxiv.org/abs/1808.00280
Autor:
Lazda, Christopher
In this short note we explain the proof that proper surjective and faithfully flat maps are morphisms of effective descent for overconvergent isocrystals. We then show how to deduce the folklore theorem that for an arbitrary variety over a perfect fi
Externí odkaz:
http://arxiv.org/abs/1706.05300