Results 211 to 220 of about 116,139 (242)
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Fréchet-Urysohn subspaces of free topological groups, II
Topology and its Applications, 2019The author completes his classification, for metrizable spaces $X$, of when the subspace $F_n(X)$ (of words of length at most $n$) of the free topological group on $X$ is Fréchet-Urysohn. The space $F_2(X)$ is Fréchet-Urysohn [\textit{K. Yamada}, Topol. Proc.
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Photonic topological subspace-induced bound states in the continuum
Optics Letters, 2023Bound states in the continuum (BICs) are intriguing localized states that possess eigenvalues embedded within the continuum of extended states. Recently, a combination of topological band theory and BIC physics has given rise to a novel form of topological matter known as topological BICs.
Wenchao Yan +3 more
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An abstract theory of topological subspaces
Mathematical Proceedings of the Cambridge Philosophical Society, 19641. Introduction. The open subsets of a topological space X form a complete Brouwerian, i.e. distributive and pseudo-complemented lattice L(X). Many topological properties of X can be formulated as properties of L(X), although, in general, X is not determined by L(X). Obvious examples are quasi-compactness and connectivity: X is quasi-compact if any set
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Existence of a topological subspace in apparently non-topological systems
2016 Progress in Electromagnetic Research Symposium (PIERS), 2016It is well known that inversion symmetry in one-dimensional periodic systems leads to the quantization of the Zak phase, which is either 0 or π. When the system has particle-hole symmetry, this topological property ensures the existence of zero-energy interface states at the interface of two bulk systems with different Zak phases.
null Yixin Xiao +2 more
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Compactness and subspace M-topologies
Soft Computing, 2022P. Rajish Kumar +2 more
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Dyadic subspaces of subgroups of topological groups
Ukrainian Mathematical Journal, 1987Let G be a compact group and let L(G) be the space of all closed subgroups of G with Chabauty topology. It is well known that L(G) is compact. The main result of this paper is the following one. Let G be a compact abelian group. The space L(G) is dyadic (i.e. L(G) is a continuous image of the Cantor cube) iff the weight of G is less then \(\aleph_ 2\).
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Invariant Subspace Topologies and Canonical Decompositions
This paper investigates the intricate relationship between the topological properties of the set of invariant subspaces of a linear operator and the operator's canonical decomposition. The set of all k-dimensional subspaces of a vector space forms a Grassmann manifold, which we endow with a natural topology induced by metrics such as the gap metric. Weopenaire +1 more source
Reduced-order methods for dynamic problems in topology optimization: A comparative study
Computer Methods in Applied Mechanics and Engineering, 2021Quhao Li +2 more
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