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31.
In the present note, we investigate schemes S in which each element s satisfies ns2 and ns*s≠2. We show that such a scheme is schurian. More precisely, we show that it is isomorphic to G//t, where G is a finite group and t an involution of G weakly closed in CG(t).
Groups G with an involution t weakly closed in CG(t) have been described in Glauberman's Z*-Theorem [G. Glauberman, Central elements in core-free groups, J. Algebra 4 (1966) 403–420] with the help of the largest normal subgroup of G having odd order. 相似文献
32.
We study bounded and unbounded *-representations of Twisted Generalized Weyl Algebras and algebras similar to them for different choices of involutions. 相似文献
33.
取向聚对苯二甲酸乙二酯纤维的非等温结晶动力学张志英,赵家森(天津纺织工学院材料科学系天津300160)关键词取向高聚物,聚对苯二甲酸乙二酯,非等温结晶,结晶动力学研究高聚物结晶动力学常用的等温方法有光透射法、密度法、显微镜法、X-射线衍射法、差示扫描... 相似文献
34.
35.
LetD be a division ring which possesses an involution a → α . Assume that
is a proper subfield ofD and is contained in the center ofD. It is pointed out that ifD is of characteristic not two, D is either a separable quadratic extension of F or a division ring of generalized quaternions
over F and that if D is of characteristic two,D is a separable quadratic extension ofF. Thus the trace map Tr:D → F, a → a + a is always surjective, which is formerly posed as an assumption in the fundamental theorem of n×n hermitian
matrices overD when n ≥ 3 and now can be deleted. WhenD is a field, the fundamental theorem of 2 × 2 hermitian matrices overD has already been proved. This paper proves the fundamental theorem of 2×2 hermitian matrices over any division ring of generalized
quaternions of characteristic not two
This research was completed during a visit to the Academy of Mathematics and System Sciences, Chinese Academy of Sciences. 相似文献
36.
Mateja Grašič 《Linear and Multilinear Algebra》2013,61(8):1007-1022
We show that the Lie algebra ? of skew-symmetric matrices with respect to either transpose or symplectic involution is zero product determined. This means that every bilinear map {·,·} from ? × ? into a vector space X is of the form {x, y} = T ([x, y]) for some linear map T provided that the following condition is fulfilled: [x, y] = 0 implies {x, y} = 0. 相似文献
37.
Tomomi Kawamura 《Topology》2007,46(1):29-38
Rasmussen introduced a knot invariant based on Khovanov homology theory, and showed that this invariant estimates the four-genus of knots. We compare his result with the sharper slice-Bennequin inequality for knots. Then we obtain a similar estimate of the Rasmussen invariant for this inequality. 相似文献
38.
Ileana Streinu 《Computational Geometry》2005,31(3):195-206
We exhibit a family of graphs which can be realized as pseudo-visibility graphs of pseudo-polygons, but not of straight-line polygons. The example is based on the characterization of vertex-edge pseudo-visibility graphs of O'Rourke and Streinu [Proc. ACM Symp. Comput. Geometry, Nice, France, 1997, pp. 119–128] and extends a recent result of the author [Proc. ACM Symp. Comput. Geometry, Miami Beach, 1999, pp. 274–280] on non-stretchable vertex-edge visibility graphs. We construct a pseudo-visibility graph for which there exists a unique compatible vertex-edge visibility graph, which is then shown to be non-stretchable. The construction is then extended to an infinite family. 相似文献
39.
Nam-Hoon Lee 《Mathematische Nachrichten》2023,296(8):3449-3458
The concept of non-Gorenstein involutions on Calabi–Yau threefolds is a higher dimensional generalization of non-symplectic involutions on K3 surfaces. We present some elementary facts about Calabi–Yau threefolds with non-Gorenstein involutions. We give a classification of the Calabi–Yau threefolds of Picard rank one with non-Gorenstein involutions, whose fixed locus is not zero-dimensional. 相似文献
40.
Berikbol T. Torebek Ramiz Tapdigoglu 《Mathematical Methods in the Applied Sciences》2017,40(18):6468-6479
A class of inverse problems for restoring the right‐hand side of a fractional heat equation with involution is considered. The results on existence and uniqueness of solutions of these problems are presented. 相似文献