首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
It is shown that necessary and sufficient conditions for a basic simplex of a point lattice in En space to be an L-simplex are equivalent to conditions imposed on the coefficients aij of the form i,j=1 n aijxixji=1 n aiixi. namely, that it should assume positive values for all possible integer values of the variables x1..., xn (excluding the obvious n+1 cases when the form is equal to 0). These conditions are obtained for n 5.Translated from Matematicheskie Zametkij Vol. 10, No. 6, pp. 659–670, December, 1971.  相似文献   

2.
Given a large weighted Hardy space we show there exists a composition operatorC with that maps from that space into the unweighted Dirichlet space and lies in every Schatten p-class for 0<p<. This is in contrast to the situation in which the image space is a smaller weighted Dirichlet space. It is known that in that case it is not possible to find such a composition operator that is bounded.This research was supported in part by a summer stipend from Bellarmine College.  相似文献   

3.
In this paper a representation by functions of the dual space of the space of (locally) slowly growing nullsolutions C p,* of a hypoelliptic PDO P (D) is given. The topology of C p,* is identical with the topology induced by D D(n+1)6. This has various topological consequences, especially: The space of slowly growing solutions is a topological sequential dense subspace of the space of locally slowly growing solutions.  相似文献   

4.
The difference sequence spaces (), c(), and c 0() were studied by Kzmaz. The main purpose of the present paper is to introduce the space bv p consisting of all sequences whose differences are in the space p , and to fill up the gap in the existing literature. Moreover, it is proved that the space bv p is the BK-space including the space p . We also show that the spaces bv p and p are linearly isomorphic for 1 p . Furthermore, the basis and the -, -, and -duals of the space bv p are determined and some inclusion relations are given. The last section of the paper is devoted to theorems on the characterization of the matrix classes (bv p : ), (bv : p ), and (bv p : 1), and the characterizations of some other matrix classes are obtained by means of a suitable relation.  相似文献   

5.
In the present article it is proved that if the Haar and Franklin systems are equivalent in a separable symmetric space E, the following condition holds: 0<EE<1, (1) where E and E are the Boyd indices of the space E. It is already known that if condition (1) is fulfilled, it follows that the Haar and Franklin systems are equivalent in the space E. Thereby, this estabishes that condition (1) is necessary and sufficient for the equivalence of the Haar and Franklin systems in E.In proving the assertion a number of interesting constructions involving Haar and Franklin polynomials are presented and upper and lower bounds on the Franklin functions applied.Translated from Matematicheskie Zametki, Vol. 52, No. 3, pp. 96–101, September, 1992.  相似文献   

6.
Let T denote a closed oriented surface and let there be given a basis 1,..., n, 1,..., n of H1 (T; ) with i · j = i · j = 0, i · j = ij as intersection numbers. Then one can construct an ordinary imbedding of T in 3-dimensional euklidian space, such that the given basis is represented by the meridians and parallels of latitude of that imbedding. If there is a given imbedding of T into an euclidian space of dimension n5, then one has a factorisation through an ordinary imbedding into 3-dimensional space, such that the given basis is represented by the meridians and parallels of latitude of that ordinary imbedding. If in the case n=4 the imbedding of T can be factorised through 3-dimensional space one has a further invariant. Besides the skewsymmetric intersection form there is a quadratic form which must take its normal form on the given basis in order to represent this basis by meridians and parallels of latitude as above.  相似文献   

7.
Let X be a reduced compact complex space and EX a -linear fibre space. Let P(E) be the associated projective variety over X and let L(E) be the canonical line bundle over P(E). Generalizing a result of Kobayashi, we prove that E carries a Finsler metric of negative curvature if and only if L(E)redP(E)red carries an Hermitian metric of negative curvature.  相似文献   

8.
If p (respectively S1) acts on a space, then under certain conditions the p (respectively Q) cohomology of each component of of the fixed point set can be generated as an algebra by at most the same number of elements as the cohomology of the space itself. It is shown below that the ideal of relations among these generators is generated by at most the number of generators in the ideal of relations defining the cohomology of the original space.  相似文献   

9.
10.
Summary LetT()=+F() be a transformation from the Wiener space to itself with the range ofF() assumed to be in the Cameron-Martin space. The absolute continuity and the density function associated withT is considered;T is assumed to be embedded in or defined through a parameterizationT t =+F t () andF t is assumed to be differentiable int. The paper deals first with the case where the range of thet-derivative ofF t () is also in the Cameron-Martin space and new representations for the Radon-Nikodym derivative and the Carleman-Fredholm determinant are derived. The case where thet-derivative ofF t is not in the Cameron-Martin space is considered next and results on the absolute continuity and the density function, under conditions which are considerably weaker than previously known conditions, are presented.The work of the second author was supported by the fund for promotion of research at the Technion  相似文献   

11.
The categorySob of sober spaces is a full isomorphismclosed reflective subcategory of the categoryT o of To-spaces (and continuous maps).SobT o is characterized by: (i) every universal morphism of the adjunction is aT o-epic embedding, and (ii) everyT o-epic embedding, whose domain is sober, is a homeomorphism.Sob is the epi-reflective hull of the Sierpinski space D inT o. A subspace of a sober space is sober, iff it is b-closed. A space is sober, iff it is a b-closed subspace of a power of D.  相似文献   

12.
For a given configuration space M and a Lie algebra G acting on M, the space V 0.0 of weakly G-invariant Lagrangians, i.e., Lagrangians whose motion equations left-hand sides are G-invariant, is studied. The problem is reformulated in terms of the double complex of Lie algebra cochains with values in the complex of Lagrangians. Calculating the cohomology of this complex by the method of spectral sequences, we arrive at the hierarchy in the space V 0.0: The double filtration {V s.}, s = 0, 1, 2, 3, 4, = 0, 1, and the homomorphisms on every space {V s.} are constructed. These homomorphisms take values in the cohomologies of the algebra G and the configuration space M. Every space {V s.} is the kernel of the corresponding homomorphism, while the space itself is defined by its physical properties.  相似文献   

13.
Summary A characterization of compact sets in Lp (0, T; B) is given, where 1P and B is a Banach space. For the existence of solutions in nonlinear boundary value problems by the compactness method, the point is to obtain compactness in a space Lp (0,T; B) from estimates with values in some spaces X, Y or B where XBY with compact imbedding XB. Using the present characterization for this kind of situations, sufficient conditions for compactness are given with optimal parameters. As an example, it is proved that if {fn} is bounded in Lq(0,T; B) and in L loc 1 (0, T; X) and if {fn/t} is bounded in L loc 1 (0, T; Y) then {fn} is relatively compact in Lp(0,T; B), p相似文献   

14.
Summary The notion of a quantum Poisson process over a quantum measure space is introduced. This process is used to construct new quantum Markov processes on the matrix algebraM n with stationary faithful state . If (, ) is the quantum measure space in question ( a von Neumann algebra and a faithful normal weight), then the semigroupe tL of transition operators on (M n , ) has generator whereu is an arbitrary unitary element of the centraliser of (M n ,).Supported by the Netherlands Organization for Scientific Research NWO  相似文献   

15.
We study a family of topologies {s}0 on the space lp, 0s is the protective topology on lp generated by the family of multipliers my:lpls, my(x)=x · y, where y ranges over the space lp and 1/p + 1/q=1/s. Here ls is taken with its standard topology generated by the norm for s 1 or a pseudonorm if 0s}0sp is strictly increasing and that all the topologies s, 0s are not locally convex when 0Matematicheskie Metody i Fiziko-Mekhanicheskie Polya, Issue 35, 1992, pp. 194–198.  相似文献   

16.
We develop the utility of Gram matrix machinery as a tool to treat the geometry of simplices in space forms. A formula relating the determinant of a normalized Gram matrix to the geometry of the simplex it represents is presented. We then apply the tools to leaf spaces, i.e. the set of degree 1 vertices of a metric tree. One main result is that for a given metric space X there exists a constant 0 < 0, such that X embeds into all hyperbolic spaces of curvature less than 0, if and only if X is a leaf space.  相似文献   

17.
ggt We consider analogoues of classical Riesz capacity C and Hausdorff measure H in a homogeneous space (X,d,µ) . We prove that, under mild regularity conditions on (X,d,µ), the usual relations between C and H hold. The key step in the proof is a version of the so called Frostman Lemma in a homogeneous space.  相似文献   

18.
Summary The purpose of this paper is to establish the existence of a solution of the Dirichlet problem for a quasilinear elliptic equation. We prove that the problem (1), (2) is solvable for all j (j=1,...), where j are eigenvalues of a linear elliptic operator that is associated with a given quasilinear elliptic operator by a limiting process. We also discuss this problem with a boundary data in L2. This leads in a natural way to the Dirichlet problem in a weighted Sobolev space.  相似文献   

19.
In this paper we give two elementary proofs for the rigidity of the complex projective space 3 with respect to global deformations.  相似文献   

20.
A set-valued mapping M from a topological vector space E into a normed vector space F is tangentially regular at a point in its graph g p h M if the Clarke tangent cone to g p h M at is equal to the Bouligand contingent cone to g p h M at . In this paper we characterize, in several cases, this tangential regularity as the directional regularity of the scalar function M defined by M (x, y) : = d(y, M(x)). The results allow us to express, in a useful formula, the subdifferential of M in terms of the normal cone to the graph of M.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号