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Benjamin J. K. Evans Susan M. Scott Antony C. Searle 《General Relativity and Gravitation》2002,34(10):1675-1684
We have developed a new tool for numerical work in General Relativity: GRworkbench. We discuss how GRworkbench's implementation of a numerically-amenable analogue to Differential Geometry facilitates the development of robust and chart-independent numerical algorithms. We consider, as an example, geodesic tracing on two charts covering the exterior Schwarzschild space-time. 相似文献
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In the absence of gamma-ray observations from space in the eighties, interest has turned to ground-based observations in the TeV energy region. The best established sources are the Crab Nebula, Cygnus X-3 and Hercules X-1. 相似文献
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Foda Omar Leclerc Bernard Okado Masato Thibon Jean-Yves Welsh Trevor A. 《Letters in Mathematical Physics》1998,43(1):31-42
A special family of partitions occurs in two apparently unrelated contexts: the evaluation of one-dimensional configuration sums of certain RSOS models, and the modular representation theory of symmetric groups or their Hecke algebras Hm. We provide an explanation of this coincidence by showing how the irreducible Hm-modules which remain irreducible under restriction to Hm_1 (Jantzen–Seitz modules) can be determined from the decomposition of a tensor product of representations sln. 相似文献
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Anthony B. Evans 《Designs, Codes and Cryptography》2006,40(1):121-130
In 1779 Euler proved that for every even n there exists a latin square of order n that has no orthogonal mate, and in 1944 Mann proved that for every n of the form 4k + 1, k ≥ 1, there exists a latin square of order n that has no orthogonal mate. Except for the two smallest cases, n = 3 and n = 7, it is not known whether a latin square of order n = 4k + 3 with no orthogonal mate exists or not. We complete the determination of all n for which there exists a mate-less latin square of order n by proving that, with the exception of n = 3, for all n = 4k + 3 there exists a latin square of order n with no orthogonal mate. We will also show how the methods used in this paper can be applied more generally by deriving several
earlier non-orthogonality results. 相似文献
6.
We demonstrate that a pair of additive quintic equations in at least 34 variables has a nontrivial integral solution, subject only to an 11-adic solubility hypothesis. This is achieved by an application of the Hardy–Littlewood method, for which we require a sharp estimate for a 33.998th moment of quintic exponential sums. We are able to employ p-adic iteration in a form that allows the estimation of such a mean value over a complete unit square, thereby providing an approach that is technically simpler than those of previous workers and flexible enough to be applied to related problems. 相似文献
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A. Craig W. H. Jacobson A. Meyer N. Welwart A. Seuthe H. N. Marr B. S. Evans G. E. F. Lundell J. A. Scherrer E. Stelling F. J. Mück A. Kling A. Lassieur L. Bertiaux C. C. Bissett P. de Pauw J. Heslinga A. Bartsch R. E. Lee W. H. Fegeley F. H. Reichel und E. Saz 《Fresenius' Journal of Analytical Chemistry》1927,71(1-2):83-90
Ohne Zusammenfassung 相似文献
10.
William Evans David Kirkpatrick 《Journal of Algorithms in Cognition, Informatics and Logic》2004,50(2):168-193
We consider the problem of restructuring an ordered binary tree T, preserving the in-order sequence of its nodes, so as to reduce its height to some target value h. Such a restructuring necessarily involves the downward displacement of some of the nodes of T. Our results, focusing both on the maximum displacement over all nodes and on the maximum displacement over leaves only, provide (i) an explicit tradeoff between the worst-case displacement and the height restriction (including a family of trees that exhibit the worst-case displacements) and (ii) efficient algorithms to achieve height-restricted restructuring while minimizing the maximum node displacement. 相似文献