共查询到20条相似文献,搜索用时 640 毫秒
1.
Asao Arai 《Mathematische Nachrichten》1999,207(1):61-77
On the boson—fermion Fock space F(H, K) associated with two complex Hilbert spaces H and K, there exists a family {Qs | S ∈ C(H, K)} of Dirac type operators, where C(H, K) is the set of densely defined closed linear operators from H to K. A theorem on the strong anticommutativity of two Dirac operators QS and QT is established. As an application, representations on F(H, K) of a supersymmetry algebra arising in a two—dimensional relativistic supersymmetric quantum field theory are discussed. 相似文献
2.
3.
In this paper, we find the orders of the Renner monoids for J-irreducible monoids K*p(G), where G is a simple algebraic group over an algebraically closed field K, and p : G → GL(V) is the irreducible representation associated with the highest root. 相似文献
4.
5.
We prove that for smooth surfaces over real closed fields, and a class of smooth projective surfaces over a real number field, the map between mod 2 algebraic and étale K-theory is an isomorphism in sufficiently large degrees. For a class of smooth projective surfaces over a real closed field, including rational surfaces, complete intersections and K3-surfaces over the real numbers, we explicate the abutment of the mod 2 motivic cohomology to algebraic K-theory spectral sequence. 相似文献
6.
On the Hochschild (co)homology of a monomial algebra given by a cyclic quiver and two zero-relations
Tomohiro Itagaki 《代数通讯》2017,45(5):2052-2073
Let K be an algebraically closed field and Γ a cyclic quiver. Xu and Wang investigated the Hochschild (co)homology groups of KΓ∕I, where I is an ideal of KΓ generated by one path. In this paper, in the case that I is an ideal of KΓ generated by two paths, we give the module structure of the Hochschild (co)homology groups of KΓ∕I. 相似文献
7.
设K是一个代数闭域,A是域K上一个有限维代数.我们利用箭图方法给出了(*)-serial incidence代数的分类. 相似文献
8.
Apostolos Thoma 《代数通讯》2013,41(7):2639-2649
Let C be a monomial curve in three dimensional projective space over an algebraically closed field K of characteristic zero . We give several necessary criterions for C to be set theoretic complete intersection. Using these criterions we get several restrictions concerning the form of the equations that define C set theoretically. 相似文献
9.
A. Caminha 《Bulletin of the Brazilian Mathematical Society》2011,42(2):277-300
In this paper we examine different aspects of the geometry of closed conformal vector fields on Riemannian manifolds. We begin
by getting obstructions to the existence of closed conformal and nonparallel vector fields on complete manifolds with nonpositive
Ricci curvature, thus generalizing a theorem of T.K. Pan. Then we explain why it is so difficult to find examples, other than
trivial ones, of spaces having at least two closed, conformal and homothetic vector fields. We then focus on isometric immersions,
firstly generalizing a theorem of J. Simons on cones with parallel mean curvature to spaces furnished with a closed, Ricci
null conformal vector field; then we prove general Bernstein-type theorems for certain complete, not necessarily cmc, hypersurfaces
of Riemannian manifolds furnished with closed conformal vector fields. In particular, we obtain a generalization of theorems
J. Jellett and A. Barros and P. Sousa for complete cmc radial graphs over finitely punctured geodesic spheres of Riemannian
space forms. 相似文献
10.
We establish a nice orthonormal frame field on a closed surface minimally immersed in a unit sphere Sn, under which the shape operators take very simple forms. Using this frame field, we obtain an interesting property K + K~N= 1 for the Gauss curvature K and the normal curvature K~N if the Gauss curvature is positive. Moreover, using this property we obtain the pinching on the intrinsic curvature and normal curvature, the pinching on the normal curvature, respectively. 相似文献
11.
该文利用Mbekhta M于1987年引入的两个子空间来研究线性算子的摄动. 证明了如下结论:设X=K(T)+W, 其中K(T), W均闭, dim[K(T)∩N(T)]< ∞. 若TWW, TW闭, 且存在闭子空间N, 使W=[W∩N(T)]N, 则: 当S∈B(X)可逆, ST= TS, SWW, 且‖S‖充分小时, T-S为上半Fredholm算子. 在上条件下, 若dimN<∞, K(T′)闭, 则T-S为Fredholm算子, 且R(T-S)=X. 相似文献
12.
We prove that any Lie algebra g over a field K of characteristic zero admitting a unique up to a constant quadratic structure is necessarily a simple Lie algebra. If the field K is algebraically closed, such condition is also sufficient. Further, a real Lie algebra g admits a unique quadratic structure if and only if its complexification gC is a simple Lie algebra over C 相似文献
13.
Kirby C. Smith 《代数通讯》2013,41(4):331-346
Let R be a noncommutative polynomial ring over the division ring K where K has center F. Then R = K[x,σ,D]where σ is a monomorphism of K and D is a σ-derivaton K. R is called dimension finite if (K: Fσ)<∞ and (K: FD)<∞ where Fσ is the subfield of F fixed under σand FD is the subfied of F of D-constants. R is algebraically closed if every nonconstant polynomial in Rfactors completely into linear factors. The algebraically closed dimension finite polynomial rings are determined. s done by reducing the problem to two classes: skew polynomial rings and differential polynomial rings. Examples algebraically closed polynomial rings which are not dimensfinite are given. 相似文献
14.
E. A. Gorin 《Mathematical Notes》1969,6(3):649-652
We consider a commutative algebra A over a field K whose algebraic closure is a finite extension of K, and describe the subalgebras of A that are of finite codimension. We solve a similar problem for the closed subalgebras of Banach algebras.Translated from Matematicheskie Zametki,Vol. 6, No. 3, pp. 321–328, September, 1969. 相似文献
15.
Subgroups of the unipotent radical of a maximal parabolic subgroup of a Chevalley group over a field K, which are normalized
by the commutator subgroup of the Levi subgroup, are described. It is shown that in the typical case, such subgroups are in
one-to-one correspondence with the closed subsets of {1, 2, ..., n} for a natural n. In the exceptional cases the classification
also involves additive subgroups of K. See the table in the paper for a detailed list of possibilities. Bibliography: 7 titles.
__________
Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 319, 2004, pp. 199–215. 相似文献
16.
In this paper, we investigate the isolated closed orbits of two types of cubic vector fields in R3 by using the idea of central projection transformation, which sets up a bridge connecting the vector field X(x) in R3 with the planar vector fields. We have proved that the cubic vector field in R3 can have two isolated closed orbits or one closed orbit on the invariant cone. As an application of this result, we have shown that a class of 3-dimensional cubic system has at least 10 isolated closed orbits located on 5 invariant cones, and another type of 3-dimensional cubic system has at least 26 isolated closed orbits located on 13 invariant cones or 26 invariant cones. 相似文献
17.
George McNinch 《Transformation Groups》2007,12(1):127-135
Let G be a connected and reductive group over the algebraically closed field K. J-P. Serre has introduced the notion of a
G-completely reducible subgroup H ⊂ G. In this paper, we give a notion of G-complete reducibility—G-cr for short—for Lie subalgebras
of Lie(G), and we show that if the closed subgroup H ⊂ G is G-cr, then Lie(H) is G-cr as well. 相似文献
18.
In this paper we describe all possible numbers of (nontrivial) invariant polynomials of the difference of two matrices with prescribed similarity classes over an algebraically closed field. 相似文献
19.
Stanisław Kasjan 《代数通讯》2013,41(10):3491-3504
Let Λ be an algebra over an algebraically closed field K of infinite transcendence degree over its prime subfield. We prove in particular that if every s-dimensional indecomposable nonprojective Λ-module is Ω-periodic (resp. DTr-periodic) then there exists a common bound for the Ω-periods (resp. DTr-periods) of s-dimensional indecomposable nonprojective Λ-modules. 相似文献
20.
Ya'acov Peterzil Anand Pillay Sergei Starchenko 《Transactions of the American Mathematical Society》2000,352(10):4421-4450
We continue the investigation of infinite, definably simple groups which are definable in o-minimal structures. In Definably simple groups in o-minimal structures, we showed that every such group is a semialgebraic group over a real closed field. Our main result here, stated in a model theoretic language, is that every such group is either bi-interpretable with an algebraically closed field of characteristic zero (when the group is stable) or with a real closed field (when the group is unstable). It follows that every abstract isomorphism between two unstable groups as above is a composition of a semialgebraic map with a field isomorphism. We discuss connections to theorems of Freudenthal, Borel-Tits and Weisfeiler on automorphisms of real Lie groups and simple algebraic groups over real closed fields.