English
Related papers

Related papers: On Kato's ramification filtration

200 papers

Over a perfect field $k$ of characteristic $p > 0$, we construct a ``Witt vector cohomology with compact supports'' for separated $k$-schemes of finite type, extending (after tensorisation with $\mathbb{Q}$) the classical theory for proper…

Algebraic Geometry · Mathematics 2007-05-23 Pierre Berthelot , Spencer Bloch , Hélène Esnault

In our earlier work \cite{KZ}, we introduced an analytic regularizability theory for smooth strictly pseudoconvex hypersurfaces in complex space. That is, we found a necessary and sufficient condition for a hypersurface to be CR-equivalent…

Complex Variables · Mathematics 2025-06-26 Ilya Kossovskiy , Dmitri Zaitsev

We study the Hurewicz map h from the homotopy groups of a spectrum X to the R-homology of its 0th space X(0), where R is a connective commutative S-algebra. We prove that the decreasing filtration of the domain of h associated to an R-based…

Algebraic Topology · Mathematics 2018-07-18 Nicholas J. Kuhn

We study the interaction between Fourier-Mukai transforms and perverse filtrations for a certain class of dualizable abelian fibrations. Multiplicativity of the perverse filtration and the "Perverse $\supset$ Chern" phenomenon for these…

Algebraic Geometry · Mathematics 2025-10-09 Davesh Maulik , Junliang Shen , Qizheng Yin

We prove that the graded quotients of the filtration by ramification groups of any henselian discrete valuation field of residue characteristic $p>0$ are $F_p$-vector spaces. We define an injection of the character group of each graded…

Algebraic Geometry · Mathematics 2024-10-08 Takeshi Saito

A field $K$ is $d$-local if there exist fields $K=k_d,...,k_0$ with $k_{i+1}$ complete discrete valuation with residue field $k_i$, and $k_0$ finite of characteristic $p$. By work of Deninger and Wingberg, the Galois cohomology of such…

Number Theory · Mathematics 2026-03-16 Antoine Galet

Let $X\to Y^0$ be an abelian prime-to-$p$ Galois covering of smooth schemes over a perfect field $k$ of characteristic $p>0$. Let $Y$ be a smooth compactification of $Y^0$ such that $Y-Y^0$ is a normal crossings divisor on $Y$. We describe…

Representation Theory · Mathematics 2014-08-15 Elmar Grosse-Klönne

We generalize the functorial quasi-isomorphism in \cite{Davis2011} from overconvergent Witt de-Rham cohomology to rigid cohomology on smooth varieties over a finite field $k$, dropping the quasi-projectiveness condition. We do so by…

Number Theory · Mathematics 2018-10-25 Nathan Lawless

In this article, we investigate the shift of Abbes and Saito's ramification filtrations of the absolute Galois group of a complete discrete valuation field of positive characteristic under a purely inseparable extension. We also study a…

Algebraic Geometry · Mathematics 2018-04-24 Haoyu Hu

We extend the results of Deligne and Illusie on liftings modulo $p^2$ and decompositions of the de Rham complex in several ways. We show that for a smooth scheme $X$ over a perfect field $k$ of characteristic $p>0$, the truncations of the…

Algebraic Geometry · Mathematics 2023-03-29 Piotr Achinger , Junecue Suh

This paper proves local-global principles for Galois cohomology groups over function fields $F$ of curves that are defined over a complete discretely valued field. We show in particular that such principles hold for $H^n(F, Z/mZ(n-1))$, for…

Number Theory · Mathematics 2013-04-11 David Harbater , Julia Hartmann , Daniel Krashen

Let $p$ be a prime. Let $V$ be a discrete valuation ring of mixed characteristic $(0,p)$ and index of ramification $e$. Let $f: G \rightarrow H$ be a homomorphism of finite flat commutative group schemes of $p$ power order over $V$ whose…

Number Theory · Mathematics 2012-07-25 Adrian Vasiu , Thomas Zink

We show that the additive higher Chow groups of regular schemes over a field induce a Zariski sheaf of pro-differential graded algebras, whose Milnor range is isomorphic to the Zariski sheaf of big de Rham-Witt complexes. This provides an…

Algebraic Geometry · Mathematics 2021-01-25 Amalendu Krishna , Jinhyun Park , with an appendix by Kay Rülling

In this paper we extend the unramified class field theory for arithmetic surfaces of K. Kato and S. Saito to the relative case. Let X be a regular proper arithmetic surface and let Y be the support of divisor on X. Let CH_0(X,Y) denote the…

Number Theory · Mathematics 2007-05-23 Alexander Schmidt

Let $X$ be an integral affine or projective hypersurface over a field $F$ of characteristic $p>0$, and let $F(X)$ denote its function field. In a recent article, Dolphin and Hoffmann obtained an explicit description of the kernel of the…

K-Theory and Homology · Mathematics 2013-11-19 Stephen Scully

Let $Y$ be a locally complete intersection over $\mathcal{O}_K$ containing a $p$-power root of unity $\zeta_p$. We classify the derived category of prismatic crystals on the absolute prismatic site of $Y$ by studying quasi-coherent…

Algebraic Geometry · Mathematics 2025-04-15 Zeyu Liu

Let $p$ be a prime integer and $F$ a field of characteristic 0. Let $X$ be the {\em norm variety} of a symbol in the Galois cohomology group $H^{n+1}(F,\mu_p^{\otimes n})$ (for some $n\geq1$), constructed in the proof of the Bloch-Kato…

Algebraic Geometry · Mathematics 2012-06-20 Nikita A. Karpenko , Alexander S. Merkurjev

In this short note we record the fact that the set of multiplicative HKR natural equivalences defined simultaneously for all derived schemes, functorialy splitting the HKR-filtration and rendering the circle action compatible with the de…

Algebraic Geometry · Mathematics 2024-11-12 Marco Robalo

For a quasi-projective scheme $X$ admitting a smooth compactification over a local field of residue characteristic $p > 0$, we construct a continuous reciprocity homomorphism from a tame class group to the abelian tame etale fundamental…

Algebraic Geometry · Mathematics 2026-01-21 Rahul Gupta , Amalendu Krishna , Jitendra Rathore

The object of study is the group of units O^\ast(X) in the coordinate ring of a normal affine variety X over an algebraically closed field k. Methods of Galois cohomology are applied to those varieties that can be presented as a finite…

Algebraic Geometry · Mathematics 2016-12-05 Timothy J. Ford