Results 11 to 20 of about 5,476,849 (277)

On Picard groups of blocks of finite groups [PDF]

Journal of Algebra, 2020
We show that the subgroup of the Picard group of a $p$-block of a finite group given by bimodules with endopermutation sources modulo the automorphism group of a source algebra is determined locally in terms of the fusion system on a defect group. We show that the Picard group of a block over the a complete discrete valuation ring ${\mathcal O}$ of ...
Boltje, R., Kessar, R., Linckelmann, M.
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Picard groups of normal surfaces [PDF]

Journal of Singularities, 2012
We study the fixed singularities imposed on members of a linear system of surfaces in P^3_C by its base locus Z. For a 1-dimensional subscheme Z \subset P^3 with finitely many points p_i of embedding dimension three and d >> 0, we determine the nature of the singularities p_i \in S for general S in |H^0 (P^3, I_Z (d))| and give a method to ...
Brevik, John, Nollet, Scott
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Analysis of a Picard modular group [PDF]

Proceedings of the National Academy of Sciences, 2006
Our main goal is to analyze the geometric and spectral properties of the Picard modular group with Gaussian integer entries acting on the two-dimensional complex hyperbolic space.
Francsics, Gábor, Lax, Peter D.
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Sequence variant analysis of RNA sequences in severe equine asthma [PDF]

PeerJ, 2018
Background Severe equine asthma is a chronic inflammatory disease of the lung in horses similar to low-Th2 late-onset asthma in humans. This study aimed to determine the utility of RNA-Seq to call gene sequence variants, and to identify sequence variants
Laurence Tessier, Olivier Côté, Dorothee Bienzle   +2 more
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Lefschetz for Local Picard groups [PDF]

Annales scientifiques de l'École normale supérieure, 2014
We prove a strengthening of the Grothendieck-Lefschetz hyperplane theorem for local Picard groups conjectured by Kollár. Our approach, which relies on acyclicity results for absolute integral closures, also leads to a restriction theorem for higher rank bundles on projective varieties in positive characteristic.
Bhatt, Bhargav, de Jong, Aise Johan
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Picard group of dual categories [PDF]

Categories and General Algebraic Structures with Applications
We provide an explicit description of the Picard group (the group of isomorphism classes of invertible objects, those that have an inverse under the tensor product) of the dual category of the category of comodules over a supergroup algebra, by using the
Adriana Mejía Castaño
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Cryptanalysing the critical group: efficiently solving Biggs's discrete logarithm problem

Journal of Mathematical Cryptology, 2009
Biggs has recently proposed the critical group of a certain class of finite graphs as a platform group for cryptosystems relying on the difficulty of the discrete log problem. The paper uses techniques from the theory of Picard groups on finite graphs to
Blackburn Simon R.
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Group actions, non-Kähler complex manifolds and SKT structures

Complex Manifolds, 2018
We give a construction of integrable complex structures on the total space of a smooth principal bundle over a complex manifold, with an even dimensional compact Lie group as structure group, under certain conditions.
Poddar Mainak, Thakur Ajay Singh
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Hecke actions on picard groups

Journal of Pure and Applied Algebra, 1982
The Hecke category \({\mathfrak H}_ G\) of a group \(G\) is defined as the category of the \({\mathbb{Z}}G\)-permutation modules \({\mathbb{Z}}G/H\) for all subgroups \(H\) of \(G\). For any given \({\mathbb{Z}}G\)-module \(M\) one defines in a natural way a contravariant additive functor \(\Phi_ M: {\mathfrak H}_ G\to\) Abelian groups, with \(\Phi_ M({
Roggenkamp, Klaus, Scott, Leonard
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Picard Groups and Refined Discrete Logarithms [PDF]

LMS Journal of Computation and Mathematics, 2005
AbstractLet K denote a number field, and G a finite abelian group. The ring of algebraic integers in K is denoted in this paper by $/cal{O}_K$, and $/cal{A}$ denotes any $/cal{O}_K$-order in K[G]. The paper describes an algorithm that explicitly computes the Picard group Pic($/cal{A}$), and solves the corresponding (refined) discrete logarithm problem.
Werner Bley, Markus Endres
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