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Compact group
Related publications (97)
Almost cyclic regular semisimple elements in irreducible representations of simple algebraic groups
Let G be a simple linear algebraic group defined over an algebraically closed field of characteristic p ≥ 0 and let φ be a nontrivial p-restricted irreducible representation of G. Let T be a maximal torus of G and s ∈ T . We say that s is Ad-regular if α(s ...
2023Lie groups as permutation groups: Ulam's problem in the nilpotent case
Ulam asked whether every connected Lie group can be represented on a countable structure. This is known in the linear case. We establish it for the first family of non-linear groups, namely in the nilpotent case. Further context is discussed to illustrate ...
WALTER DE GRUYTER GMBH2022The rationales that underlie modal practices
Encouraging a modal shift from individual transportation to less polluting modes such as public transport, walking and cycling, is now a key recommendation of the UN to reach the goals set by the Paris Agreement. Achieving this ambitious goal requires a de ...
2022A b-symplectic slice theorem
In this article, motivated by the study of symplectic structures on manifolds with boundary and the systematic study of b-symplectic manifolds started in Guillemin, Miranda, and Pires Adv. Math. 264 (2014), 864-896, we prove a slice theorem for Lie group a ...
WILEY2022A combinatorial proof of a sumset conjecture of Furstenberg
We give a new proof of a sumset conjecture of Furstenberg that was first proved by Hochman and Shmerkin in 2012: if is irrational and and are - and -invariant subsets of , respectively, then $\dim_\text{ ...
2021On complete reducibility of tensor products of simple modules over simple algebraic groups
Let G be a simply connected simple algebraic group over an al- gebraically closed field k of characteristic p > 0. The category of rationalG-modules is not semisimple. We consider the question of when the tensorproduct of two simple G-modules L(λ) and L(μ) ...
2021Spherical birational sheets in reductive groups
We classify the spherical birational sheets in a complex simple simply-connected algebraic group. We use the classification to show that, when G is a connected reductive complex algebraic group with simply-connected derived subgroup, two conjugacy classes ...
ACADEMIC PRESS INC ELSEVIER SCIENCE2021Almost impossible E_8 and Leech lattices
We start this short note by introducing two remarkable mathematical objects: the E8E8 root lattice Lambda8Lambda8 in 8-dimensional Euclidean space and the Leech lattice Lambda24Lambda24 in 24-dimensional space. These two lattices stand out among their lat ...
2021Smaller, Faster & Lighter KNN Graph Constructions
Rachid Guerraoui, Anne-Marie Kermarrec, Olivier Ruas
We propose GoldFinger, a new compact and fast-to-compute binary representation of datasets to approximate Jaccard’s index. We illustrate the effectiveness of GoldFinger on the emblematic big data problem of K-Nearest-Neighbor (KNN) graph construction and s ...
2020On compact representations of Voronoi cells of lattices
Matthias Schymura, Christoph Hunkenschröder
In a seminal work, Micciancio and Voulgaris (SIAM J Comput 42(3):1364-1391, 2013) described a deterministic single-exponential time algorithm for the closest vector problem (CVP) on lattices. It is based on the computation of the Voronoi cell of the given ...
SPRINGER HEIDELBERG2020