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Disjoint frames are interesting frames in Hilbert spaces, which were introduced by Han and Larson in [4]. In this article, we use disjoint frames to construct frames. In particular, we obtain some conditions for the linear combinations of frames to be frames where the coefficients in the combination may be operators. Our results generalize the corresponding results obtained by Han and Larson. Finally, we provide some examples to illustrate our constructions. 相似文献
104.
Ahmed Hegazi 《代数通讯》2013,41(12):5237-5256
The paper is devoted to the study of annihilator extensions of Jordan algebras and suggests new approach to classify nilpotent Jordan algebras, which is analogous to the Skjelbred–Sund method for classifying nilpotent Lie algebras [2, 4, 15]. Subsequently, we have classified nilpotent Jordan algebras of dimension up to four. 相似文献
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It is shown that the minimum value of the permanent on the n× ndoubly stochastic matrices which contain at least one zero entry is achieved at those matrices nearest to Jn in Euclidean norm, where Jn is the n× nmatrix each of whose entries is n-1 . In case n ≠ 3 the minimum permanent is achieved only at those matrices nearest Jn ; for n= 3 it is achieved at other matrices containing one or more zero entries as well. 相似文献
108.
We describe the sub-bimodules of matrix bimodules over two structural matrix rings. Structural matrix bimodules arise as particular such sub-bimodules, and we discuss when such a bimodule is faithful or indecomposable. As an application, we obtain a large class of rings whose Jordan isomorphisms are either ring isomorphisms or ring anti-isomorphisms. Complete upper block triangular matrix rings over 2-torsion-free indecomposable rings are elements of this class. 相似文献
109.
ABSTRACTAn algebra with identities a(bc)?=?b(ac), (ab)c?=?(ac)b is called bicommutative. We construct list of identities satisfied by commutator and anti-commutator products in a free bicommutative algebra. We give criterions for elements of a free bicommutative algebra to be Lie or Jordan. 相似文献
110.
Kurt Meyberg 《代数通讯》2013,41(11):1311-1326
In finite dimensional Lie algebras, Jordan algebras, and other algebraic structures the study of derivations has been facilitated by having a nontrivial trace formula on hand (see for example [?]) . Tuere is no common pattern in proving these trace formulas, they all depend on the underlying structures. In this note we derive such a trace formula for finite dimensional central simple Jordan pairs. We use it to determine all derivations the Killing form and the dimensions of the derivation algebras of the Jordan pairs. Dur primary tool is a Trace Reduction Formula. 相似文献