共查询到20条相似文献,搜索用时 15 毫秒
1.
We prove that the composition S(u1, …, un) of a multilinear multiple 2-summing operator S with 2-summing linear operators uj is nuclear, generalizing a linear result of Grothendieck.
Both authors were partially supported by DGICYT grant BMF2001-1284. 相似文献
2.
T. Fernández 《Monatshefte für Mathematik》2005,145(2):95-96
We give an easy proof of a result in [1] generalizing the well-known Borsuks non-retraction theorem. 相似文献
3.
Assume that X⊆R?Q, and each clopen-valued lower semicontinuous multivalued map has a continuous selection . Our main result is that in this case, X is a σ-space. We also derive a partial converse implication, and present a reformulation of the Scheepers Conjecture in the language of continuous selections. 相似文献
4.
We analyze relations between various forms of energies (reciprocal capacities), the transfinite diameter, various Chebyshev
constants and the so-called rendezvous or average number. The latter is originally defined for compact connected metric spaces
(X,d) as the (in this case unique) nonnegative real number r with the property that for arbitrary finite point systems {x
1, …, x
n
} ⊂ X, there exists some point x ∈ X with the average of the distances d(x,x
j
) being exactly r. Existence of such a miraculous number has fascinated many people; its normalized version was even named “the magic number”
of the metric space. Exploring related notions of general potential theory, as set up, e.g., in the fundamental works of Fuglede
and Ohtsuka, we present an alternative, potential theoretic approach to rendezvous numbers. 相似文献
5.
Manfred Stoll 《Monatshefte für Mathematik》2005,144(2):131-139
Let B denote the unit ball in n, n 1, and let and
denote the volume measure and gradient with respect to the Bergman metric on B. In the paper we consider the weighted Dirichlet spaces
,
, and weighted Bergman spaces
,
,
, of holomorphic functions f on B for which
and
respectively are finite, where
and
The main result of the paper is the following theorem.Theorem 1. Let f be holomorphic on B and
.(a) If
for some
, then
for all p,
, with
.(b) If
for some p,
, then
for all
with
. Combining Theorem 1 with previous results of the author we also obtain the following.Theorem 2. Suppose
is holomorphic in B. If
for some p,
, and
, then
. Conversely, if
for some p,
, then the series in * converges. 相似文献
6.
Ferenc Móricz 《Monatshefte für Mathematik》2006,148(1):51-59
We extend some recent results of S. A. Telyakovskii on the uniform boundedness of the partial sums of Fourier series of functions
of bounded variation to periodic functions of two variables, which are of bounded variation in the sense of Hardy. As corollaries,
we obtain the classical Parseval formula, the convergence theorem of the series involving the sine Fourier coefficients, and
a lower estimate of the best approximation by trigonometric polynomials in the metric of L in a sharpened version.
This research was supported by the Hungarian National Foundation for Scientific Research under Grants TS 044 782 and T 046
192. 相似文献
7.
Bibasic sequences of Singer are used to show that ℓ1 embeds complementably in the Banach space X if and only if X* contains a non-relatively compact strong Dunford–Pettis set. Spaces of operators and strongly additive vector measures are
also discussed.
An erratum to this article is available at . 相似文献
8.
The object of our investigations are isotropic convex bodies , centred at the origin and normed to volume one, in arbitrary dimensions. We show that a certain subset of these bodies –
specified by bounds on the second and fourth moments – is invariant under forming ‘expanded joinsrsquo;. Considering a body
K as above as a probability space and taking , we define random variables on K. It is known that for subclasses of isotropic convex bodies satisfying a ‘concentration of mass property’, the distributions
of these random variables are close to Gaussian distributions, for high dimensions n and ‘most’ directions . We show that this ‘central limit property’, which is known to hold with respect to convergence in law, is also true with
respect to -convergence and -convergence of the corresponding densities.
Received: 21 March 2001 / in final form: 17 October 2001 / Published online: 4 April 2002 相似文献
9.
Gaven J. Martin 《Mathematische Annalen》2002,324(2):329-340
A uniformly quasiregular mapping, is a mapping of the m-sphere with the property that it and all its iterates have uniformly bounded distortion. Such maps are rational with respect to
some bounded measurable conformal structure and there is a Fatou-Julia type theory associated with the dynamical system obtained
by iterating these mappings. We begin by investigating the analogue of Siegel's theorem on the local conjuga cy of rotational
dynamics. We are led to consider the analytic continuation properties of solutions to the highly nonlinear first order Beltrami
systems. We reduce these problems to a central and well known conjecture in the theory of transformation groups; namely the
Hilbert-Smith conjecture, which roughly asserts that effective transformation groups of manifolds are Lie groups. Our affirmative
solution to this problem then implies unique analytic continuation and Siegel's theorem.
Received: 14 September 2000 / Revised version: 23 November 2001 / Published online: 5 September 2002
RID="*"
ID="*" Research supported in part by grants from the Marsden Fund and Royal Society (NZ). 相似文献
10.
L. Olsen 《Monatshefte für Mathematik》2005,146(2):143-157
For a probability measure μ on a subset of
, the lower and upper Lq-dimensions of order
are defined by
We study the typical behaviour (in the sense of Baire’s category) of the Lq-dimensions
and
. We prove that a typical measure μ is as irregular as possible: for all q ≥ 1, the lower Lq-dimension
attains the smallest possible value and the upper Lq-dimension
attains the largest possible value. 相似文献
11.
Box and Packing Dimensions of Typical Compact Sets 总被引:1,自引:0,他引:1
Let (X,ρ) be a complete metric space and let dim A be the upper box dimension of the set . We show that packing dimension of the typical (in the sense of Baire category) compact set is at least . (Received 27 March 2000; in revised form 5 June 2000) 相似文献
12.
Let be a complete metric space and let be the space of all probability Borel measures on X. We give some estimations of the upper and lower box dimensions of the typical (in the sense of Baire category) measure in
.
Received 29 November 2000; in final form 8 January 2002 相似文献
13.
Filippo Tolli 《Monatshefte für Mathematik》2001,133(2):163-173
We present a local limit theorem for a measure on the special linear group with entries in a local field.
(Received 20 March 2000; in revised form 8 September 2000) 相似文献
14.
Let be a fixed point free group given by the presentation
where and are relative prime numbers, t = /s and s = gcd( – 1,), and is the order of modulo . We prove that if (1) = 2, and (2) is embeddable into the multiplicative group of some skew field, then is circular. This means that there is some additive group N on which acts fixed point freely, and |((a)+b)((c)+d)| 2 whenever a,b,c,d N, a0c, are such that (a)+b(c)+d. 相似文献
15.
By estimating the subgroup numbers associated with various classes of large groups, we exhibit a number of new phenomena in the theory of subgroup growth. 相似文献
16.
The aim of this paper is to present some results about spin structures on flat manifolds. We prove that any finite group can
be the holonomy group of a flat spin manifold. Moreover, we shall give some methods of constructing spin structures related
to the holonomy representation. 相似文献
17.
In this paper, we show that the Boothby-Wang fibration of the Iwasawa manifold
is an unstable critical point for the energy of a distribution.
The work of the first author is partially supported by TBAG-?G/2. 相似文献
18.
Changyu Xia 《Monatshefte für Mathematik》2005,146(2):159-168
Let Sn(c) denote the n-dimensional Euclidean sphere of constant sectional curvature c and denote by CPn(c) the complex projective space of complex dimension n and of holomorphic sectional curvature c. In this paper, we obtain some characterizations of the manifolds S2(c) × S2(c′), S4(c) × S4(c′), CP2(c) × CP2(c′) by their spectrum. 相似文献
19.
We give explicit formulae for the numerical index of some (real) polyhedral spaces of dimension two. Concretely, we calculate the numerical index of a family of hexagonal norms, two families of octagonal norms and the family of norms whose unit balls are regular polygons with an even number of vertices. 相似文献
20.
In this article, we present new bounds for the zeros of polynomials depending on some estimates for the spectral norms and the spectral radii of the square and the cube of the Frobenius companion matrix. 相似文献