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871.
N. Yu. Makarenko 《Siberian Mathematical Journal》2007,48(1):95-111
We prove that if a (?/n?)-graded Lie algebra L = ? i=0 n?1 L i has d nontrivial components L i and the null component L 0 has finite dimension m, then L has a homogeneous solvable ideal of derived length bounded by a function of d and of codimension bounded by a function of m and d. An analogous result holds also for the (?/n?)-graded Lie rings L = ? i=0 n?1 with few nontrivial components L i if the null component L 0 has finite order m. These results generalize Kreknin’s theorem on the solvability of the (?/n?)-graded Lie rings L = ? i=0 n?1 L i with trivial component L 0 and Shalev’s theorem on the solvability of such Lie rings with few nontrivial components L i . The proof is based on the method of generalized centralizers which was created by E. I. Khukhro for Lie rings and nilpotent groups with almost regular automorphisms of prime order [1], as well as on the technique developed in the work of N. Yu. Makarenko and E. I. Khukhro on the almost solvability of Lie algebras with an almost regular automorphism of finite order [2]. 相似文献
872.
V. F. Molchanov 《Acta Appl Math》2007,99(3):321-337
We define canonical representations R
λ
,
, for the Lobachevsky space ℒ=G/K of dimension n−1 where G=SO0(n−1,1), K=SO(n−1), as the restriction to G of maximal degenerate series representations of the overgroup
. We determine explicitly the interaction of Lie operators of
with operators intertwining canonical representations and representations of G associated with a cone.
Supported by the Russian Foundation for Basic Research: grants No. 05-01-00074a and No. 05-01-00001a, the Netherlands Organization
for Scientific Research (NWO): grant 047-017-015, the Scientific Program “Devel. Sci. Potent. High. School”: project RNP.2.1.1.351
and Templan No. 1.2.02. 相似文献
873.
874.
A. Chakrabarti V. K. Dobrev S. G. Mihov 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,58(2):135-136
We refute a recent claim in the literature [Czech. J. Phys. 56, 1191 (2006)] of a “new"
quantum deformation of GL(2). 相似文献
875.
Héctor Suárez 《代数通讯》2017,45(10):4569-4580
Pre-Koszul and Koszul algebras were defined by Priddy [15]. There exist some relations between these algebras and the skew PBW extensions defined in [8]. In [24] we gave conditions to guarantee that skew PBW extensions over fields it turns out homogeneous pre-Koszul or Koszul algebra. In this paper we complement these results defining graded skew PBW extensions and showing that if R is a finite presented Koszul 𝕂-algebra then every graded skew PBW extension of R is Koszul. 相似文献
876.
《Journal of Nonlinear Mathematical Physics》2013,20(3):283-298
Invariant linearization criteria for square systems of second-order quadratically nonlinear ordinary differential equations (ODEs) that can be represented as geodesic equations are extended to square systems of ODEs cubically nonlinear in the first derivatives. It is shown that there are two branches for the linearization problem via point transformations for an arbitrary system of second-order ODEs and its reduction to the simplest system. One is when the system is at most cubic in the first derivatives. One obtains the equivalent of the Lie conditions for such systems. We explicitly solve this branch of the linearization problem by point transformations in the case of a square system of two second-order ODEs. Necessary and sufficient conditions for linearization to the simplest system by means of point transformations are given in terms of coefficient functions of the system of two second-order ODEs cubically nonlinear in the first derivatives. A consequence of our geometric approach of projection is a rederivation of Lie's linearization conditions for a single second-order ODE and sheds light on more recent results for them. In particular we show here how one can construct point transformations for reduction to the simplest linear equation by going to the higher space and just utilizing the coefficients of the original ODE. We also obtain invariant criteria for the reduction of a linear square system to the simplest system. Moreover these results contain the quadratic case as a special case. Examples are given to illustrate our results. 相似文献
877.
878.
《Journal of Nonlinear Mathematical Physics》2013,20(3):461-474
Standard (Arnold–Liouville) integrable systems are intimately related to complex rotations. One can define a generalization of these, sharing many of their properties, where complex rotations are replaced by quaternionic ones, and more generally by the action of a Clifford group. Such a generalization is not limited to integrable systems but — in the quaternionic case — goes over to a generalization of standard Hamilton dynamics. 相似文献
879.
N. Filonov 《Journal of Functional Analysis》2011,260(10):2902-2932
We show that a bounded operator A on a Hilbert space belongs to a certain set associated with its self-commutator [A?,A], provided that A−zI can be approximated by invertible operators for all complex numbers z. The theorem remains valid in a general C?-algebra of real rank zero under the assumption that A−zI belong to the closure of the connected component of unity in the set of invertible elements. This result implies the Brown-Douglas-Fillmore theorem and Huaxin Lin?s theorem on almost commuting matrices. Moreover, it allows us to refine the former and to extend the latter to operators of infinite rank and other norms (including the Schatten norms on the space of matrices). The proof is based on an abstract theorem, which states that a normal element of a C?-algebra of real rank zero satisfying the above condition has a resolution of the identity associated with any open cover of its spectrum. 相似文献
880.
Osamu Hatori 《Journal of Mathematical Analysis and Applications》2011,376(1):84-93
We prove that an isometry T between open subgroups of the invertible groups of unital Banach algebras A and B is extended to a real-linear isometry up to translation between these Banach algebras. While a unital isometry between unital semisimple commutative Banach algebras need not be multiplicative, we prove in this paper that if A is commutative and A or B are semisimple, then (T(eA))−1T is extended to an isometric real algebra isomorphism from A onto B. In particular, A−1 is isometric as a metric space to B−1 if and only if they are isometrically isomorphic to each other as metrizable groups if and only if A is isometrically isomorphic to B as a real Banach algebra; it is compared by the example of ?elazko concerning on non-isomorphic Banach algebras with the homeomorphically isomorphic invertible groups. Isometries between open subgroups of the invertible groups of unital closed standard operator algebras on Banach spaces are investigated and their general forms are given. 相似文献