Results 161 to 170 of about 10,041,383 (202)

The Continuity of Inverse in Groups

Moscow University Mathematics Bulletin, 2022
This article is a contribution to the question under which conditions a paratopological group is a topological group. For that the author introduces the concept of a \(\Delta\)-Baire space. A topological space \(X\) is a \(\Delta\)-Baire space if for every set \(P\subseteq X\times X\) containing the diagonal \(\Delta:=\{(x,x):x\in X\}\) and having the ...
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Products of subsets of groups by their inverses

Beiträge zur Algebra und Geometrie / Contributions to Algebra and Geometry, 2013
In the paper under review, a group \(G\) is called a \(\mathcal P\)-group (\(\mathcal P_k\)-group for some integer \(k>0\)) if each finite subset \(X\) of \(G\) (each subset \(X\) of size \(|X|\leq k\)) satisfies \(|XX^{-1}|=|X^{-1}X|\). The authors classify all \(\mathcal P\)-groups (in Theorem 7.4) as two infinite families: the abelian groups and ...
Marcel Herzog, Gil Kaplan, LONGOBARDI, Patrizia, MAJ, Mercede   +3 more
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INVERSIONS IN CLASSICAL WEYL GROUPS

Communications in Contemporary Mathematics, 2007
We introduce inversions for classical Weyl group elements and relate them, by counting, to the length function, root systems and Schubert cells in flag manifolds. Special inversions are those that only change signs in the Weyl groups of types Bn, Cnand Dn.
Ding, K, Wu, S
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ON THE GROUP INVERSE FOR THE SUM OF MATRICES

Journal of the Australian Mathematical Society, 2013
AbstractLet${ \mathbb{K} }^{m\times n} $denote the set of all$m\times n$matrices over a skew field$ \mathbb{K} $. In this paper, we give a necessary and sufficient condition for the existence of the group inverse of$P+ Q$and its representation under the condition$PQ= 0$, where$P, Q\in { \mathbb{K} }^{n\times n} $.
Bu, Changjiang, Zhou, Xiuqing, Ma, Liang, Zhou, Jiang   +3 more
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On the Fundamental Group of Inverse Limits

Bulletin of the Malaysian Mathematical Sciences Society, 2016
A set valued function \(f:X\longrightarrow 2^{Y}\) into the nonempty closed subsets of \(Y\) is upper semi-continuous (usc) if for each \(x \in X\) and each open set \(V \subset Y\) containing the set \(f (x)\), there exists an open set \(U\subset X\) such that \(x \in U\) and \(\bigcup_{u\in U} f (u) \subset V\).
Vavpetič, Aleš, Virk, Žiga
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Displacement structure of group inverses

Numerical Linear Algebra with Applications, 2004
AbstractA matrix A is said to possess an UV‐displacement structure if rank(AU – VA) is small compared with the rank of A. Estimates for the rank AgV – UAg are presented, where Ag is the group inverse of A. Copyright © 2004 John Wiley & Sons, Ltd.
Yimin Wei 0001, Michael K. Ng 0001
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Individuals, Groups and Inverse Discrimination

Analysis, 1973
M ANY morally sensitive people find themselves faced with the following dilemma. On the one hand, they are persuaded by the argument that if being black, e.g., is morally irrelevant, then it is morally irrelevant and no more justifies favourable inverse discrimination than it justifies unfavourable discrimination.
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Group inverse sampling: An economical approach to inverse sampling

Environmetrics, 2017
Inverse sampling is an adaptive design in the sense that the final sampling effort during a search for rare events will depend on what is found during the survey. Conventional inverse sampling (CIS) designs successively select individual sampling units to find, for example, the kth rare event.
Panahbehagh, Bardia, Smith, David R.
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An Efficient Factorization for the Group Inverse

SIAM Journal on Algebraic Discrete Methods, 1987
The author considers singular square \(n\times n\) matrices A which are of index one (rank(A \(2)=rank(A)=n-m)\). The value m is assumed much smaller than n. The author also considers block systems of k copies of A along the diagonal \((k\ll n)\), the identity on the subdiagonal, and zero elsewhere.
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Inverse Renormalization Group of Disordered Systems.

CoRR, 2023
We propose inverse renormalization group transformations to construct approximate configurations for lattice volumes that have not yet been accessed by supercomputers or large-scale simulations in the study of spin glasses. Specifically, starting from lattices of volume $V=8^{3}$ in the case of the three-dimensional Edwards-Anderson model we employ ...
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