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81.
82.
In this paper, we present some necessary and sufficient conditions under which an irreducible polynomial is self-reciprocal (SR) or self-conjugate-reciprocal (SCR). By these characterizations, we obtain some enumeration formulas of SR and SCR irreducible factors of , , over , which are just open questions posed by Boripan et al. (2019). We also count the numbers of Euclidean and Hermitian LCD constacyclic codes and show some well-known results on Euclidean and Hermitian self-dual constacyclic codes in a simple and direct way. 相似文献
83.
84.
Every translation invariant positive definite Hermitian bilinear functional on the Gel'fand-Shilov space sMpMp(n×nK) of general type S is of the form B(,) = (x)(x)d(x), , sMpMp (n), where is a positive {M}-tempered measure, i.e., for every > 0 exp[-M(|x|)] d(x) < . To prove this we prove Schwartz kernel theorem for {M}-tempered ultradistributions and need Bochner-Schwartz theorem for {M}-tempered ultradistributions. Our result includes most of the quasianalytic cases. Also, we obtain parallel results for the case of Beurling type (Mp. 相似文献
85.
Let Г be a torsion-free uniform lattice of SU(m, 1), m > 1. Let G be either SU(p, 2) with p ≥ 2, ${{\rm Sp}(2,\mathbb {R})}Let Г be a torsion-free uniform lattice of SU(m, 1), m > 1. Let G be either SU(p, 2) with p ≥ 2, or SO(p, 2) with p ≥ 3. The symmetric spaces associated to these G’s are the classical bounded symmetric domains of rank 2, with the exceptions of SO*(8)/U(4) and SO*(10)/U(5). Using the correspondence
between representations of fundamental groups of K?hler manifolds and Higgs bundles we study representations of the lattice
Г into G. We prove that the Toledo invariant associated to such a representation satisfies a Milnor-Wood type inequality and that
in case of equality necessarily G = SU(p, 2) with p ≥ 2m and the representation is reductive, faithful, discrete, and stabilizes a copy of complex hyperbolic space (of maximal possible
induced holomorphic sectional curvature) holomorphically and totally geodesically embedded in the Hermitian symmetric space
SU(p, 2)/S(U(p) × U(2)), on which it acts cocompactly. 相似文献
86.
Byeong Moon Kim Poo-Sung Park 《Proceedings of the American Mathematical Society》2008,136(9):3041-3044
It is shown that over infinitely many imaginary quadratic fields there exists a Hermitian lattice in all even ranks which is generated by its minimal vectors but which is not generated by minimal vectors.
87.
Let be an imaginary quadratic field with ring of integers , where is a square free integer such that , and let is a linear code defined over . The level theta function of is defined on the lattice , where is the natural projection. In this paper, we prove that:
i) for any such that , and have the same coefficients up to ,
ii) for , determines the code uniquely,
iii) for , there is a positive dimensional family of symmetrized weight enumerator polynomials corresponding to .
88.
引进一个关于Goppa几何码(代数几何码)最小距离界的一个新方法.应用Maharaj的思想(即用显示基来近似表达Riemann-Roch空间)到Goppa几何码的最小距离的界上去.通过厄米特曲线上的代数几何码的一类例子,来证明标准的几何码的下界在某些情形下可以被显著地改进.进一步地,我们给出了这些码的最小距离上界,并说明了我们的下界非常接近这个上界. 相似文献
89.
Tatjana Petek 《Linear algebra and its applications》1999,290(1-3):167-191
The general form of a continuous mapping φ acting on the real vector space of all n × n complex Hermitian or real symmetric matrices, and preserving spectrum and commutativity, is derived. It turns out that φ is either linear or its image forms a commutative set. 相似文献
90.
We relate so-called spin factors and generalized Hermitian (GH-) algebras, both of which are partially ordered special Jordan
algebras. Our main theorem states that positive-definite spin factors of dimension greater than one are mathematically equivalent
to generalized Hermitian algebras of rank two.
S. Pulmannová was supported by Research and Development Support Agency under the contract No. APVV-0071-06, grant VEGA 2/0032/09
and Center of Excellence SAS, CEPI I/2/2005. 相似文献