Results 1 to 10 of about 1,234 (221)
Von Staudt's theorem revisited [PDF]
, 2013 We establish a version of von Staudt's theorem on mappings which preserve harmonic quadruples for projective lines over (not necessarily commutative) rings with "sufficiently many" units, in particular 2 has to be a unit.Comment: More typos ...
Havlicek, Hans
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Preserving Distances in Very Faulty Graphs [PDF]
, 2017 Preservers and additive spanners are sparse (hence cheap to store) subgraphs that preserve the distances between given pairs of nodes exactly or with some small additive error, respectively. Since real-world networks are prone to failures, it makes sense
Bodwin, Greg +3 more
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Spectrum-preserving additive maps
Linear Algebra and its Applications, 1991 Let \(X,Y\) be Banach spaces over the complex field, and \(B(X),B(Y)\) denote the algebra of bounded linear operators on \(X,Y\) respectively. A map \(\Phi: B(X)\to B(Y)\) is said to be spectrum preserving if \(\sigma(\Phi(T))=\sigma(T)\), for every \(T\in B(X)\). The authors prove the following main result.
Omladič, Matjaž, Šemrl, Peter
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Orthogonality preserving property for pairs of operators on Hilbert $C^*$-modules
, 2021 We investigate the orthogonality preserving property for pairs of mappings on inner product $C^*$-modules extending existing results for a single orthogonality-preserving mapping.
Frank, Michael +2 more
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Orthogonal forms and orthogonality preservers on real function algebras [PDF]
, 2013 We initiate the study of orthogonal forms on a real C$^*$-algebra. Motivated by previous contributions, due to Ylinen, Jajte, Paszkiewicz and Goldstein, we prove that for every continuous orthogonal form $V$ on a commutative real C$^*$-algebra, $A ...
Antonio, Jorge J. Garcés, M. Peralta
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Orthogonally additive and orthogonally multiplicative holomorphic functions of matrices [PDF]
, 2014 Let $H:M_m\to M_m$ be a holomorphic function of the algebra $M_m$ of complex $m\times m$ matrices. Suppose that $H$ is orthogonally additive and orthogonally multiplicative on self-adjoint elements.
Bu, Qingying +2 more
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Distributed Construction of Purely Additive Spanners
, 2016 This paper studies the complexity of distributed construction of purely additive spanners in the CONGEST model. We describe algorithms for building such spanners in several cases.
Censor-Hillel, Keren +3 more
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Reachability Preservers: New Extremal Bounds and Approximation Algorithms
, 2023 We abstract and study \emph{reachability preservers}, a graph-theoretic primitive that has been implicit in prior work on network design. Given a directed graph $G = (V, E)$ and a set of \emph{demand pairs} $P \subseteq V \times V$, a reachability ...
Abboud, Amir, Bodwin, Greg
core
Antioxidants versus Food Antioxidant Additives and Food Preservatives [PDF]
Antioxidants, 2019 Natural and processed foods are fragile and can become unpalatable and/or rotten. The processed food industry uses preservatives to enable distribution, even to different continents, and to extend the useful life of their products. Preservatives impede oxidation, a mandatory step in rotting, either by aerobic or anaerobic mechanisms.
Rafael Franco +2 more
openaire +5 more sources
Linear rank preservers of tensor products of rank one matrices
, 2016 Let $n_1,\ldots,n_k $ be integers larger than or equal to 2. We characterize linear maps $\phi: M_{n_1\cdots n_k}\rightarrow M_{n_1\cdots n_k}$ such that $${\mathrm rank}\,(\phi(A_1\otimes \cdots \otimes A_k))=1\quad\hbox{whenever}\quad{\mathrm rank ...
Huang, Zejun, Shi, Shiyu, Sze, Nung-Sing
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