Results 11 to 20 of about 1,089 (246)
Discrete Symmetries in Translation Invariant Cosmological Models [PDF]
General Relativity and Gravitation, 2001 17 pages, 8 ps figures. To appear in Gen.
Sigbjørn Hervik
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Gromov translation algebras over discrete trees are exchange rings [PDF]
Transactions of the American Mathematical Society, 2003 The authors show that the Gromov translation ring of a discrete tree over a von Neumann regular ring is an exchange ring. This result provides a new source of exchange rings, including the algebras \(G(0)\) of the countable-infinite matrices over a field of constant bandwidth, hence for any \(r\) in \([0,1]\), the growth algebras \(G(r)\) are exchange ...
Ara, P., O'Meara, K. C., Perera, F.
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Universal convex covering problems under translations and discrete rotations [PDF]
Advances in Geometry, 2023 Abstract We consider the smallest-area universal covering of planar objects of perimeter 2 (or equivalently, closed curves of length 2) allowing translations and discrete rotations. In particular, we show that the solution is an equilateral triangle of height 1 when translations and discrete rotations of π are allowed.
Jung, Mook Kwon +3 more
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Completeness in $L^1 (\mathbb R)$ of discrete translates
Revista Matemática Iberoamericana, 2006 We characterize, in terms of the Beurling-Malliavin density, the discrete spectra \Lambda\subset\mathbb R for which a generator exists, that is a function \varphi\in L^1(\mathbb R)
Bruna , Joaquim +2 more
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On the Translation Parameter Problem for Discrete Variables [PDF]
The Annals of Mathematical Statistics, 1951 For any chance variable $x = (x_1,\cdots,x_N)$ having known distribution, the translation parameter estimation problem is to estimate an unknown constant $h$, having observed $y = (x_1 + h,\cdots,x_N + h)$. Extending the work of Pitman [2], Girshick and Savage [1] have, for any loss function depending only on the error of estimate, described an ...
David Blackwell
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Completeness of uniformly discrete translates in LP(ℝ) [PDF]
Journal d'Analyse MathématiqueAbstract We construct a real sequence {λ n } n=1 ∞ satisfying λ n = n + o(1), and a Schwartz function f on ℝ, such that for any N the system of translates {f(x − λ n )},
Nir Lev
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partial translation algebras for certain discrete metric spaces [PDF]
, 2010 The notion of a partial translation algebra was introduced by Brodzki, Nibloand Wright in [11] to provide an analogue of the reduced group C*-algebrafor metric spaces. Such an algebra is constructed from a partial translationstructure, a structure which any bounded geometry uniformly discrete metricspace admits; we prove that these structures restrict ...
Rosemary Johanna Putwain
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A rotation and translation invariant discrete saliency network [PDF]
Biological Cybernetics, 2003 We describe a neural network that enhances and completes salient closed contours in images. Our work is different from all previous work in three important ways. First, like the input provided to primary visual cortex (V1) by the lateral geniculate nucleus (LGN), the input to our computation is isotropic.
Williams, Lance R., Zweck, John W.
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Discrete Lorentz symmetry and discrete spacetime translational symmetry in two- and three-dimensional crystals [PDF]
Journal of Physics: Condensed Matter, 2020 As is well known, crystals have discrete space translational symmetry. It was recently noticed that one-dimensional crystals possibly have discrete Poincar symmetry, which contains discrete Lorentz and discrete time translational symmetry as well. In this paper, we classify the discrete Poincar groups on two- and three-dimensional Bravais lattices.
Xiuwen Li +3 more
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Garside groups are strongly translation discrete
Journal of Algebra, 2007 The Garside group, as a generalization of braid groups and Artin groups of finite types, is defined as the group of fractions of a Garside monoid. We show that the semidirect product of Garside monoids is a Garside monoid. We use the semidirect product $\mathbb Z\ltimes G^n$ of the infinite cyclic group $\mathbb Z$ and the cartesian product $G^n$ of a ...
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