Results 1 to 10 of about 59,724 (184)
Torus actions, Morse homology, and the Hilbert scheme of points on affine space [PDF]
Épijournal de Géométrie Algébrique, 2021 We formulate a conjecture on actions of the multiplicative group in motivic homotopy theory. In short, if the multiplicative group G_m acts on a quasi-projective scheme U such that U is attracted as t approaches 0 in G_m to a closed subset Y in U, then ...
Burt Totaro
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Fundamental Groupoids for Graphs [PDF]
Categories and General Algebraic Structures with Applications, 2022 In recent years several notions of discrete homotopy for graphs have been introduced, including a notion of ×-homotopy due to Dochtermann. In this paper, we define a ×-homotopy fundamental groupoid for graphs, and prove that it is a functorial ×-homotopy
Tien Chih, Laura Scull
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Adjointness of Suspension and Shape Path Functors [PDF]
Mathematics Interdisciplinary Research, 2021 In this paper, we introduce a subcategory ∼Sh* of Sh* and obtain some results in this subcategory. First we show that there is a natural bijection Sh(∑(X, x), (Y,y))≅Sh((X,x),Sh((I, Ī),(Y,y))), for every (Y,y)∈ ~Sh* and (X,x)∈ Sh*. By this fact, we prove
Tayyebe Nasri +2 more
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Mathematische Nachrichten, 2020 AbstractIn this note on coarse geometry we revisit coarse homotopy. We prove that coarse homotopy indeed is an equivalence relation, and this in the most general context of abstract coarse structures. We introduce (in a geometric way) coarse homotopy groups.
Paul D. Mitchener +2 more
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Frontiers in Bioscience-Landmark, 2021 Background: Adolescent and young adult cancer patients (AYACPs) experience a high incidence of psychological distress. However, the effect of psychological distress on the functional connectivity between the hemispheres in AYACPs remains unknown.
Jianfei Xie +8 more
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A survey of homotopy nilpotency and co-nilpotency
Pracì Mìžnarodnogo Geometričnogo Centru, 2020 We review known and state some new results on homotopy nilpotency and co-nilpotency of spaces. Next, we take up the systematic study of homotopy nilpotency of homogenous spaces G/K for a Lie group G and its closed subgroup K < G.
Marek Golasinski
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Homotopy Groups of Spheres and Lipschitz Homotopy Groups of Heisenberg Groups [PDF]
Geometric and Functional Analysis, 2014 We provide a sufficient condition for the nontriviality of the Lipschitz homotopy group of the Heisenberg group, $ _m^{Lip}(H_n)$, in terms of properties of the classical homotopy group of the sphere, $ _m(S^n)$. As an application we provide a new simplified proof of the fact that $ _n^{Lip}(H_n)\neq 0$, $n=1,2,...$, and we prove a new result that $
Hajłasz, Piotr +2 more
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Sparse Group Feature Selection by Weighted Thresholding Homotopy Method
IEEE Access, 2020 In this paper, we investigate the sparse group feature selection problem, in which covariates posses a grouping structure sparsity at the level of both features and groups simultaneously.
Jinglan Wu, Huating Huang, Wenxing Zhu
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A (Discrete) Homotopy Theory for Geometric Spaces
Journal of Mathematics, 2023 We define the concepts of homotopy and fundamental group for geometric spaces as a generalization of metric spaces, digital spaces, and graphs; then, we compare them with corresponding concepts in these spaces.
Asieh Pourhaghani, Hamid Torabi
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A remark on the contactomorphism group of overtwisted contact spheres
Comptes Rendus. Mathématique, 2020 We show the existence of elements of infinite order in some homotopy groups of the contactomorphism group of overtwisted spheres. It follows in particular that the contactomorphism group of some high dimensional overtwisted spheres is not homotopically ...
Fernández, Eduardo, Gironella, Fabio
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