English
Related papers

Related papers: Le lemme d'Abhyankar perfectoide

200 papers

We introduce a concept of approximately invertible elements in non-unital normed algebras which is, on one side, a natural generalization of invertibility when having approximate identities at hand, and, on the other side, it is a direct…

Functional Analysis · Mathematics 2021-06-18 Kevin Esmeral , Hans G. Feichtinger , Ondrej Hutník , Egor A. Maximenko

We establish various properties of the p-adic algebraic K-theory of smooth algebras over perfectoid rings living over perfectoid valuation rings. In particular, the p-adic K-theory of such rings is homotopy invariant, and coincides with the…

K-Theory and Homology · Mathematics 2022-03-15 Benjamin Antieau , Akhil Mathew , Matthew Morrow

We give an introduction to the valuation theoretical phenomenon of "defect", also known as "ramification deficiency". We describe the role it plays in deep open problems in positive characteristic: local uniformization (the local form of…

Commutative Algebra · Mathematics 2013-04-05 Franz-Viktor Kuhlmann

We introduce a class of Banach algebras of generalized matrices and study the existence of approximate units, ideal structure, and derivations of them.

Functional Analysis · Mathematics 2016-05-16 Maysam Maysami Sadr

A new proof of the decomposition theorem is established using a relation with a version of the local purity theorem of Deligne and Gabber adapted to complex algebraic varieties.

Algebraic Geometry · Mathematics 2013-12-03 Fouad Elzein , Lê Dung Trang

Following Weinstein, Boyarchenko-Weinstein and Imai-Tsushima, we construct a family of affinoids in the Lubin-Tate perfectoid space and formal models such that the cohomology of the reduction of each formal model realizes the local…

Number Theory · Mathematics 2020-03-10 Kazuki Tokimoto

In this paper, a new invariant was built towards the classification of separable C*-algebras of real rank zero, which we call latticed total K-theory. A classification theorem is given in terms of such an invariant for a large class of…

Operator Algebras · Mathematics 2024-08-29 Qingnan An , Chunguang Li , Zhichao Liu

In this note, we study the $p$-complete topological cyclic homology of the affine line relative to a ring $A$ which is smooth over a perfectoid ring $R$. Denoting by $NTC(A; \mathbb{Z}_p)$ the spectrum which measures the failure of…

K-Theory and Homology · Mathematics 2024-10-10 Elden Elmanto , Noah Riggenbach

We adapt methods coming from additive combinatorics in groups to the study of linear span in associative unital algebras. In particular, we establish for these algebras analogues of Diderrich-Kneser's and Hamidoune's theorems on sumsets and…

Combinatorics · Mathematics 2015-06-24 Vincent Beck , Cédric Lecouvey

We extend Kolchin's results on linear dependence over projective varieties in the constants, to linear dependence over arbitrary complete differential varieties. We show that in this more general setting, the notion of linear dependence…

Algebraic Geometry · Mathematics 2014-07-10 James Freitag , Omar Leon Sanchez , William Simmons

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 prove that the Khovanov-Lauda-Rouquier algebras $R_\alpha$ of finite type are (graded) affine cellular in the sense of Koenig and Xi. In fact, we establish a stronger property, namely that the affine cell ideals in $R_\alpha$ are…

Representation Theory · Mathematics 2013-10-17 Alexander Kleshchev , Joseph Loubert

We prove that for any compact quasi-smooth strictly $k$-analytic space $X$ there exist a finite extension $l/k$ and a quasi-\'etale covering $X'\to X\otimes_kl$ such that $X'$ possesses a strictly semistable formal model. This extends a…

Algebraic Geometry · Mathematics 2016-10-07 Michael Temkin

We prove that if two nonzero homomorphisms from the Cuntz algebra O_infinity to a purely infinite simple C*-algebra have the same class in KK-theory, and if either both are unital or both are nonunital, then they are approximately unitarily…

funct-an · Mathematics 2008-02-03 Huaxin Lin , N. Christopher Phillips

Let $(R,\mathfrak{m}, k)$ be a strictly local normal $k$-domain of positive characteristic and $P$ be a prime divisor on $X=\text{Spec } R$. We study the Galois category of finite covers over $X$ that are at worst tamely ramified over $P$…

Algebraic Geometry · Mathematics 2023-03-29 Javier Carvajal-Rojas , Axel Stäbler

We consider degenerations of all simple Lie algebras of exceptional type obtained by embedding into affine Lie algebras. We give a filtration to consider this as an abelianisation of the original Lie algebra. We then show that the…

Representation Theory · Mathematics 2022-11-29 Shreepranav Varma Enugandla

For a projective variety $X$ defined over a non-Archimedean complete non-trivially valued field $k$, and a semipositive metrized line bundle $(L, \phi)$ over it, we establish a metric extension result for sections of $L^{\otimes n}$ from a…

Algebraic Geometry · Mathematics 2019-04-09 Yanbo Fang

Khovanov-Lauda-Rouquier algebras $R_\theta$ of finite Lie type are affine quasihereditary with standard modules $\Delta(\pi)$ labeled by Kostant partitions of $\theta$. Let $\Delta$ be the direct sum of all standard modules. It is known…

Representation Theory · Mathematics 2019-06-28 Doeke Buursma , Alexander Kleshchev , David J. Steinberg

For a certain class of abelian categories, we show how to make sense of the "Euler characteristic" of an infinite projective resolution (or, more generally, certain chain complexes that are only bounded above), by passing to a suitable…

Category Theory · Mathematics 2014-02-26 Pramod N. Achar , Catharina Stroppel

We introduce abelian framed bicategories, which are particular framed bicategories that are locally abelian, and show that they are suitable for developing homology and cohomology theories for directed structures. This means in particular…

Category Theory · Mathematics 2026-02-05 Augustin Albert , Jérémy Dubut , Eric Goubault