207,445 research outputs found
On Real Solutions of the Equation Φ\u3csup\u3e\u3cem\u3et\u3c/em\u3e\u3c/sup\u3e (\u3cem\u3eA\u3c/em\u3e) = 1/\u3cem\u3en\u3c/em\u3e J\u3csub\u3e\u3cem\u3en\u3c/em\u3e\u3c/sub\u3e
For a class of n × n-matrices, we get related real solutions to the matrix equation Φt (A) = 1/n Jn by generalizing the approach of and applying the results of Zhang, Yang, and Cao [SIAM J. Matrix Anal. Appl., 21 (1999), pp. 642–645]. These solutions contain not only those obtained by Zhang, Yang, and Cao but also some which are neither diagonally nor permutation equivalent to those obtained by Zhang, Yang, and Cao. Therefore, the open problem proposed by Zhang, Yang, and Cao in the cited paper is solved
A New Lower Bound for the Distinct Distance Constant
The reciprocal sum of Zhang sequence is not equal to the Distinct Distance
Constant. This note introduces a -sequence with larger reciprocal sum, and
provides a more precise estimation of the reciprocal sums of Mian-Chowla
sequence and Zhang sequence.Comment: 4 pages, 3 ancillary table
The non-perturbative constraint on sea quarks --the strange sea quarks in the nucleon and the soft pion contribution at high energy--
The mean charge sum rule for the light sea quarks in the nucleon which holds
under the same theoretical footing as the modified Gottfried sum rule shows
that a usual parameterization of the strange sea quark distribution
underestimate its contribution in the small region. We give a discussion of
the soft pion contribution at high energy as a possible explanation of the
saturation of the sum rule and show that it naturally explains why the strange
sea quark is suppressed in the region above while it becomes
abundant below it.Comment: 5 pages, Talk presented at the International Conference on Flavor
Physics(ICFP2001) in Zhang-Jia-Jie City,Hunan,China,June 200
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