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1.
 We prove that if a symmetric submarkovian semigroup (T t ) t>0 satisfies an estimate of the form
where ϕ is an increasing C 1 -diffeomorphism of [0,+∞) with subexponential growth, then a suitable function of its infinitesimal generator is bounded from L p (M) to L q (M) for 1<p<q<+∞, and that a weak converse holds true if p=2. In the special case where ϕ(t)=Ct μ for small t and ϕ(t)=C′ exp(ct ν ) for large t, μ>0, c>0, 0<ν<1, one obtains a sharp and explicit result, which applies for instance to sublaplacians on solvable unimodular Lie groups with exponential growth. Received: 29 June 2001 / Published online: 1 April 2003 Mathematics Subject Classifications (2000): 47D06, 58J35, 43A80 Research supported by the Italian M.U.R.S.T., fondi 60%, the Italian GNAFA, and the European Commission (European TMR Network ``Harmonic Analysis' 1998–2001, Contract ERBFMRX-CT97-0159).  相似文献   

2.
We deal with the sum of sequence spaces. Then we apply these results to characterize matrix transformations mapping between s h,l (λ, μ) = s α 0((Δ − λI) h ) + s β (c)((Δ − μI) l ) and s γ . Among other things the aim of this paper is to reduce the set (s h,l (λ, μ), s γ to a set of the form S τ,γ .   相似文献   

3.
孙承雄 《数学杂志》2014,34(1):151-154
本文研究亚纯函数的值分布问题.利用值分布理论,获得了一个带精简密指量的模分布的不等式,改进了Xu和Yang等人的结果.  相似文献   

4.
We classify all connected subgroups of SO(2, n) that act irreducibly on ℝ2, n . Apart from SO 0(2, n) itself these are U(1, n/2), SU(1, n/2), if n even, S 1 · SO(1, n/2) if n even and n ≥ 2, and SO 0(1, 2) for n = 3. Our proof is based on the Karpelevich Theorem and uses the classification of totally geodesic submanifolds of complex hyperbolic space and of the Lie ball. As an application we obtain a list of possible irreducible holonomy groups of Lorentzian conformal structures, namely SO 0(2, n), SU(1, n), and SO 0(1, 2).  相似文献   

5.
基于对广义系统、泛导、泛对称、泛箱原理、泛系相对性提出了新的分析模式与新的相对数学化的简化强化的定义,发展了泛系方法论与泛系相对论的框架与理法,具体内容涉及相对普适的数学化的泛系,200类对偶,对偶转化,泛对称转化,泛系辩证,八畴方法,泛系数学方法,广义量化,逼近转化原则,泛等价定理,供求分析,思维实验,广义灰色系统,等等  相似文献   

6.
Samuel A. Ilori 《K-Theory》1989,2(5):623-624
We use the work of Karoubi and Mudrinski on the real Grothendieck's groups of certain complex projective bundles to show that the torsion of the KO i groups of G 3( n ), n odd, are related to the known torsion of the KO i groups of G2( n ).  相似文献   

7.
We obtain the necessary conditions for the embedding H p ω e L (1≤p∞) with convex modulus of continuity ω in terms of this modulus. In the case p=1 these conditions are also sufficient.  相似文献   

8.
9.
Considering the Navier–Stokes equations in W ì \mathbbRn\Omega \subset {\mathbb{R}}^n, we prove the asymptotic stability for weak solutions in the marginal class uC B (0, ∞; L n ) with arbitrary initial and external perturbations.  相似文献   

10.
论文利用极大刻画方法介绍了带一般参数的Hardy空间.作为特殊情况, 它们包含了经典Hp空间, Hardy-Lorentz 空间Hp,q和广义的Hardy-Lorentz空间Hp(φ).  相似文献   

11.
12.
Topological Hochschild homology is calculated for the rings /p[x]/(f(x)) (where p is prime and f(x) /p[x] any polynomial), [x]/(x n) and [x]/(x n–1). A spectral sequence argument is used for calculating the homology of the topological Hochschild homology spectrum, from which its stable homotopy structure can be read off since the spectrum is known for a priori reasons to be a restricted product of Eilenberg-MacLane spectra.  相似文献   

13.
The purpose of this paper is to investigate the refinement equations of the form
where the vector of functions ϕ=(ϕ 1..., ϕ r ) T is in (L p (ℝ s )) r , 1⩽p⩽∞, a(α), α∈ℤ s is a finitely supported sequence of r × r matrices called the refinement mask, and M is an s × s integer matrix such that lim→∞ M-n = 0. In order to solve the refinement equation mentioned above, we start with a vector of compactly supported functions φ 0∈(L p (ℝ s )) r and use the iteration schemes f n :=Q a n φ 0, n=1,2,..., where Q n is the linear operator defined on (L p (ℝ s )) r given by
This iteration scheme is called a subdivision scheme or cascade algorithm. In this paper, we characterize the Lp-convergence of subdivision schemes in terms of the p-norm joint spectral radius of a finite collection of some linear operators determined by the sequence a and the set B restricted to a certain invariant subspace, where the set B is a complete set of representatives of the distinct cosets of the quotient group ℤs/Mℤs containing 0.  相似文献   

14.
崔晓梅  刘丽波  高寒 《数学杂志》2014,34(6):1149-1154
本文研究了矩阵方程X+A*X-αA+B*X-βB=I在α,β∈(0,1]时的正定解.利用单调有界极限存在准则,构造三种迭代算法,获得了方程的正定解,拓宽了此类方程的求解方法.数值算例说明算法的可行性.  相似文献   

15.
16.
祁博亮 《数学通讯》2012,(Z3):122-123
在一本初等数论的书上,我看到这样一个问题:判断6465+6564是素数还是合数?可以想象这是一个很大的数,需要比较巧的方法才能判定.书上是这样解答的:根据费马小定理,如果a和p互素,p是素数,则ap-1≡1(mod p).  相似文献   

17.
18.
Results on singular products of the distributions x ± -p and x -p for natural p are derived, when the products are balanced so that their sum exists in the distribution space. These results follow the pattern of a known distributional product published by Jan Mikusiski in 1966. The results are obtained in the Colombeau algebra of generalized functions, which is the most relevant algebraic construction for tackling nonlinear problems of Schwartz distributions.  相似文献   

19.
 Let k be a positive integer and α be a real number, and for if the fractional part of is <1/2 and e n =−1 if it is ≥1/2. The pseudorandom properties of the sequence are studied. As measures of pseudorandomness, the regularity of the distribution relative to arithmetic progressions and the correlation are used. Here the special cases k=1 and k=2 are studied (while the case k>2 will be studied in the sequel).  相似文献   

20.
In the present paper, for a boundary value problem with noncoordinated degeneration of the data and a singularity in the solution, we show that the R ν -generalized solution belongs to the weighted space W 2,ν+gb 2+κ+1/κ+2 (Ω, δ)(κ > 0). Original Russian Text ? V.A. Rukavishnikov, E.V. Kuznetsova, 2009, published in Differentsial’nye Uravneniya, 2009, Vol. 45, No. 6, pp. 894–898.  相似文献   

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