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101.
Double graded ideals and simplicity of elementary unitary Lie algebra eu
n
(R,−, γ) and Steinberg unitary Lie algebra stu
n
(R,−, γ) are characterized, where R is a unital involutory associative algebra over a field F of characteristic zero, n ⩾ 5. 相似文献
102.
NormAttainabilityofElementaryOperatorsandDerivationsJiGuoting(吉国兴)andDeffengke(杜鸿科)(DepartmentofMathematics,ShaanxiNormalUniv... 相似文献
103.
Jan Johannsen 《Mathematical Logic Quarterly》1998,44(2):205-215
We define a property of substructures of models of arithmetic, that of being length-initial, and show that sharply bounded formulae are absolute between a model and its length-initial submodels. We use this to prove independence results for some weak fragments of bounded arithmetic by constructing appropriate models as length-initial submodels of some given model. 相似文献
104.
We show that if M is a stable unsuperstable homogeneous structure, then for most κ ? |M|, the number of elementary submodels of M of power κ is 2κ. 相似文献
105.
M. Barraa 《Linear algebra and its applications》2002,350(1-3):289-292
Let E,F be two Banach spaces and let S be a symmetric norm ideal of L(E,F). For AL(F) and BL(E) the generalized derivation δS,A,B is the operator on S that sends X to AX−XB. A bounded linear operator is said to be convexoid if its (algebraic) numerical range coincides with the convex hull of its spectrum. We show that δS,A,B is convexoid if and only if A and B are convexoid. 相似文献
106.
Antonín Sochor 《Mathematical Logic Quarterly》1994,40(1):51-60
Proceeding in the theory with extensionality, comprehension for classes, existence of the empty set and the assumption the addition of one element to a set makes again a set (others usual set-theoretical operations are not required) we show a week assumption which guarantees existence of a saturated elementary extension (with absolute ?) of the system of hereditarily finite sets. Mathematics Subject Classification: 03C62, 03C50, 03E70. 相似文献
107.
Christian Opitz Hans Müller Adnan Kodlaa 《Monatshefte für Chemie / Chemical Monthly》1990,121(5):331-338
Summary Using the cluster model of the silicon (111) surface we derive by means of EHT calculations a mechanism of reactive plasma etching in the system F/Si including diffusion processes. Species SiF2 are found to be the primary etching products at the surface. SiF4 is formed with high probability in the gas phase. 相似文献
108.
Shinsaku Fujita 《Theoretical chemistry accounts》1992,82(6):473-498
Summary The elementary superposition theorems are presented for enumerating chemical compounds that contain achiral and chiral ligands. Subduced cycle indices (SCI-CF), partial cycle indices (PCI-CF), and cycle indices (CI-CF) with chirality fittingness are defined by starting from unit subduced cycle indices with chirality fittingness (USCI-CF). All of these indices afford generating functions that are proved to be applicable to combinatorial enumeration. In addition, the concept of elementary superposition with and without chirality fittingness is proposed to provide the elementary superposition theorems. These theorems provide us with a new methodology of enumerating compounds, in which the numbers of isomers are obtained without relying on generating functions and are itemized with respect to molecular formulas (weights) and symmetries. The operation is defined on the basis of the elementary superposition. Thereby, we derive superposition theorems concerning the PCI-CFs and the CI-CFs. These are applicable to combinatorial enumeration. 相似文献
109.
王晓明 《数学年刊A辑(中文版)》2016,37(4):397-404
设g=W_1是特征p3的代数闭域k上的Witt代数.本文确定了g的极大基本子代数.进一步具体给出了最大维数的基本子代数的G共轭类,这里G是g的自同构群.从而证明了最大维数为(p-1)/2的基本子代数射影簇E((p-1)/2,g)是不可约的且是一维的.更进一步,证明了E(1,g)是不可约的,具有维数p-2,而E(2,g)是等维的,共有(p-3)/2个不可约分支,且每个不可约分支的维数是p-4.而当3≤r≤(p-3)/2时,E(r,g)是可约的.给出了E(r,g)(3≤r≤(p-3)/2)维数的一个下界. 相似文献
110.
The basic motivation behind this work is to tie together various computational complexity classes, whether over different
domains such as the naturals or the reals, or whether defined in different manners, via function algebras (Real Recursive
Functions) or via Turing Machines (Computable Analysis). We provide general tools for investigating these issues, using two
techniques we call approximation and lifting. We use these methods to obtain two main theorems. First, we provide an alternative proof of the result from Campagnolo et al.
(J Complex 18:977–1000, 2002), which precisely relates the Kalmar elementary computable functions to a function algebra over
the reals. Second, we build on that result to extend a result of Bournez and Hainry (Theor Comput Sci 348(2–3):130–147, 2005),
which provided a function algebra for the
real elementary computable functions; our result does not require the restriction to functions. In addition to the extension, we provide an alternative approach to the proof. Their proof involves simulating
the operation of a Turing Machine using a function algebra. We avoid this simulation, using a technique we call lifting, which allows us to lift the classic result regarding the elementary computable functions to a result on the reals. The two
new techniques bring a different perspective to these problems, and furthermore appear more easily applicable to other problems
of this sort.
相似文献