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41.
Dragoljub Keckic 《Proceedings of the American Mathematical Society》2000,128(11):3369-3377
We prove the orthogonality of the range and the kernel of an important class of elementary operators with respect to the unitarily invariant norms associated with norm ideals of operators. This class consists of those mappings , , where is the algebra of all bounded Hilbert space operators, and , , , are normal operators, such that , and . Also we establish that this class is, in a certain sense, the widest class for which such an orthogonality result is valid. Some other related results are also given.
42.
A. A. Zakharenko 《Pramana》2007,69(4):617-629
In this work, the experimental results of the creation of the second non-dispersive Zakharenko wave (C
ph = C
g ≠ 0) in the negative roton branch (the so-called second sound) of the bulk elementary excitations (BEEs) energy spectra are
introduced. Several BEE signals detected by a bolometer situated in the isotopically pure liquid helium-II at low temperatures
∼100 mK are shown, which give evidence of negative roton creation in the liquid by helium atomic beams striking the liquid
surface. The negative roton signals were clearly distinguished by the following ways: the negative roton signal created by
helium atomic beams appeared earlier than the positive roton signal created by the beams, and presence of both positive and
negative roton signals together. It is natural that the negative roton creation by the beams requires the 4He-atom energies ∼12 K, while the positive roton creation by the atomic beams requires energies ∼35 K. Therefore, successive
increase in the heater power resulting in an increase in the 4He-atom energies gives solid evidence that the negative rotons are first created in the liquid by the helium atomic beams.
相似文献
43.
Eon-Kyung Lee 《代数通讯》2013,41(3):1121-1139
In this article, we show that for every abelian subgroup H of a Garside group, some conjugate g ?1 Hg consists of ultra summit elements and the centralizer of H is a finite index subgroup of the normalizer of H. Combining with the results on translation numbers in Garside groups, we obtain an easy proof of the algebraic flat torus theorem for Garside groups and solve several algorithmic problems concerning abelian subgroups of Garside groups. 相似文献
44.
K. V. Kostousov 《Algebra and Logic》2008,47(2):118-124
We point out a countable set of pairwise nonisomorphic Cayley graphs of the group ℤ4 that are limit for finite minimal vertex-primitive graphs admitting a vertex-primitive automorphism group containing a regular
Abelian normal subgroup.
Supported by RFBR grant No. 06-01-00378.
__________
Translated from Algebra i Logika, Vol. 47, No. 2, pp. 203–214, March–April, 2008. 相似文献
45.
用群的共轭类个数刻画了交换群,同时用一个很简洁的方法重新证明了Frobenius G提出的一个著名问题:对于一个固定的数自然数n,共轭类数为n的有限群,在同构的意义下是有限的. 相似文献
46.
一类特殊的无限非正则p-群 总被引:1,自引:1,他引:0
利用有限正则p-群和局部幂零群的理论,得到:如果G是可解的非正则p-群,且G的每一个无限真子群是正则的,那么群G是秩为p-1的可除阿贝尔群被循环群的扩张. 相似文献
47.
Wolfgang Rump 《Applied Categorical Structures》2009,17(2):153-174
We give a axiomatic treatment of the absolute in the category of all topological spaces and characterize it as a cover with
respect to the full subcategory of extremally disconnected spaces. As an application, we obtain the strongly projectable hull
of an abelian l-group as a unique lifting of the absolute of its spectrum.
Dedicated to B. V. M. 相似文献
48.
令t(G)为有限阿贝尔群G的单因子个数.本文得到了∑|G|≤xt(G)带有更好余项的渐近公式. 相似文献
49.
Frederik Herzberg 《Mathematical Logic Quarterly》2008,54(2):167-175
This article establishes the existence of a definable (over ZFC), countably saturated nonstandard enlargement of the superstructure over the reals. This nonstandard universe is obtained as the union of an inductive chain of bounded ultrapowers (i.e. bounded with respect to the superstructure hierarchy). The underlying ultrafilter is the one constructed by Kanovei and Shelah [10]. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
50.