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51.
We prove that a finite unary algebra with at least two operation symbols is a homomorphic image of a (finite) subdirectly
irreducible algebra if and only if the intersection of all its subalgebras which have at least two elements is nonempty.
While working on this paper the first and the third authors were partially supported by the Grant Agency of the Czech Republic,
grant #201/02/0594, and by the institutional grant MSM0021620839; the second author was supported by the Ministry of Science,
Technologies and Development of Republic of Serbia, grant no. 1227. 相似文献
52.
The famous 1960's construction of Golod and Shafarevich yields infinite dimensional nil, but not nilpotent, algebras. However, these algebras have exponential growth. Here, we construct an infinite dimensional nil, but not locally nilpotent, algebra which has polynomially bounded growth.
53.
Jānis Cīrulis 《Central European Journal of Mathematics》2007,5(2):264-279
The infimum of elements a and b of a Hilbert algebra are said to be the compatible meet of a and b, if the elements a and b are compatible in a certain strict sense. The subject of the paper will be Hilbert algebras equipped with the compatible meet operation, which normally is partial. A partial lower semilattice is shown to be a reduct of such an expanded Hilbert algebra i ?both algebras have the same ?lters.An expanded Hilbert algebra is actually an implicative partial semilattice (i.e., a relative subalgebra of an implicative semilattice),and conversely.The implication in an implicative partial semilattice is characterised in terms of ?lters of the underlying partial semilattice. 相似文献
54.
55.
56.
证明了TUHF代数丁上的Lie导子L形如D l.其中D是T上的结合导子,l是从T到它的中心Z上的线性映射且零化T中的括积. 相似文献
57.
为了精确计算束流在离子光学系统中的传输,用Visual FORTRAN 6.5语言编写了一个计算程序,长约13000行. 此程序可以计算由三圆筒单透镜、三膜片单透镜、双元筒透镜、均匀场静电加速管、磁四极透镜、六极磁铁、静电四极透镜、偏转磁铁、螺线管透镜、ExB~正交电磁场分析器、静电偏转器、漂浮管、QWR(Quarter Wave Resonators)和SLR(Split Loop Resonators)射频加速元件等元件任意组成的离子光学系统. 粒子轨迹的计算可精确到三级近似. 粒子的分布类型也可以有多种选择. 程序具有最优化计算功能,即可以自动调整元件的参数,以实现所需要的光学条件. 各元件之后的横向和纵向相图以及系统的束流包络线以图形方式显示在屏幕上. 相似文献
58.
K. N. Ponomarev 《Algebra and Logic》2007,46(4):263-273
Various classes of non-associative algebras possessing the property of being rigid under abstract isomorphisms are studied.
Supported by RFBR grant No. 06-01-00159a.
__________
Translated from Algebra i Logika, Vol. 46, No. 4, pp. 483–502, July–August, 2007. 相似文献
59.
We define nontempered (exponential growth) function spaces on the Lie group ax+b which are stable under some left-invariant (convergent) star product. The techniques used to achieved the latter come from symmetric spaces geometry and star representation theory. 相似文献
60.
David Fryberger 《Foundations of Physics Letters》1990,3(4):379-386
Issues raised by W. A. Rodrigues, Jr. are discussed.1. This is not a new result; see,e.g., Rohrlich.(3)
2. A typographical error in Eq. (77) is corrected here: The productj A in the right-hand parentheses was erroneously transcribed in Ref. (2) as
A.3. I define electromagnetic fieldF = A to be that generated by electric charges and the magnetoelectric fieldG = M to be that generated by magnetic monopoles:F F +5
G.
4. Rodrigues, on the other hand, takes the position that the importance of the Lagrangian formulation should be downgraded if not discarded altogether: ... it is redundant to look for Lagrangians.(1)
5. In fact, he reformulates it using the language of differential forms.6. It is interesting to observe that this bilinear form has the additional virtue of being appropriate for dealing with the monopolecharge parity question, which was pointed out long ago.(14)
7. In fact, even mathematics looks to Nature for its authority.(16) There is evidence that Rodrigues does not understand this concept.(17) 相似文献