Results 1 to 10 of about 5,692 (84)
Advances in Mathematics, 1989 Let \(a(t)=1+\sum_{n=1}a_ nt^ n \in {\mathbb{Z}}[[t]]\) be a formal power series with integral coefficients. The authors establish isomorphisms between: the Burnside ring \({\hat \Omega}(C)\) of the infinite cyclic group C, the Grothendieck ring \(\Lambda(Z)\) [\textit{A. Grothendieck}, Bull. Soc. Math.
Dress, Andreas, Siebeneicher, Christian
openaire +3 more sources
The basic geometry of Witt vectors, I: The affine case [PDF]
, 2015 We give a concrete description of the category of etale algebras over the ring of Witt vectors of a given finite length with entries in an arbitrary ring.
Borger, James
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Boolean Witt vectors and an integral Edrei-Thoma theorem [PDF]
, 2015 A subtraction-free definition of the big Witt vector construction was recently given by the first author. This allows one to define the big Witt vectors of any semiring.
Borger, James, Grinberg, Darij
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The basic geometry of Witt vectors, II: Spaces [PDF]
, 2015 This is an account of the algebraic geometry of Witt vectors and arithmetic jet spaces. The usual, "p-typical" Witt vectors of p-adic schemes of finite type are already reasonably well understood.
Borger, James
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On the geometry of lattices and finiteness of Picard groups [PDF]
, 2019 Let (K, O, k) be a p-modular system with k algebraically closed and O unramified, and let Λ be an O-order in a separable K-algebra. We call a Λ-lattice L rigid if Ext1Λ(L, L) = 0, in analogy with the definition of rigid modules over a finite-dimensional ...
Eisele, F.
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Springer's theorem for tame quadratic forms over Henselian fields [PDF]
, 2010 A quadratic form over a Henselian-valued field of arbitrary residue characteristic is tame if it becomes hyperbolic over a tamely ramified extension. The Witt group of tame quadratic forms is shown to be canonically isomorphic to the Witt group of graded
Elomary, Mohamed Abdou +1 more
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Euler class groups, and the homology of elementary and special linear groups [PDF]
, 2016 We prove homology stability for elementary and special linear groups over rings with many units improving known stability ranges. Our result implies stability for unstable Quillen K-groups and proves a conjecture of Bass. For commutative local rings with
Schlichting, Marco
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Universal deformation rings and tame blocks [PDF]
, 2013 Let k be an algebraically closed field of positive characteristic, and let W be the ring of infinite Witt vectors over k. Suppose G is a finite group and B is a block of kG of infinite tame representation type. We find all finitely generated kG-modules V
B. Schaefer +3 more
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Almost purity and overconvergent Witt vectors [PDF]
, 2014 In a previous paper, we stated a general almost purity theorem in the style of Faltings: if R is a ring for which the Frobenius maps on finite p-typical Witt vectors over R are surjective, then the integral closure of R in a finite \'etale extension of R[
Davis, Christopher, Kedlaya, Kiran S.
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Witt Vector Rings and the Relative de Rham Witt Complex [PDF]
, 2015 In this paper we develop a novel approach to Witt vector rings and to the (relative) de Rham Witt complex. We do this in the generality of arbitrary commutative algebras and arbitrary truncation sets.
Cuntz, Joachim, Deninger, Christopher
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