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1.
Let H be a product of countably infinite number of copies of an uncountable Polish space X. Let Σξ be the class of Borel sets of additive class ξ for the product of copies of the discrete topology on X (the Polish topology on X), and let . We prove in the Lévy-Solovay model that
for 1 ≤ ξ < ω 1.  相似文献   

2.
In 1939 Agnew presented a series of conditions that characterized the oscillation of ordinary sequences using ordinary square conservative matrices and square multiplicative matrices. The goal of this paper is to present multidimensional analogues of Agnew’s results. To accomplish this goal we begin by presenting a notion for double oscillating sequences. Using this notion along with square RH-conservative matrices and square RH-multiplicative matrices, we will present a series of characterization of this sequence space, i.e. we will present several necessary and sufficient conditions that assure us that a square RH-multiplicative(square RH-conservative) be such that
for each double real bounded sequences {s k;l } where
In addition, other implications and variations are also presented.   相似文献   

3.
The third-order nonlinear dispersion PDE, as the key model,
((0.1))
is studied. Two Riemann’s problems for (0.1) with the initial data S (x) = ∓ sgn.x create shock (u(x, t) ≡ S (x)) and smooth rarefaction (for the data S +) waves (see [16]). The concept of “δ-entropy” solutions and others are developed for establishing the existence and uniqueness for (0.1) by using stable smooth δ-deformations of shock-type solutions. These are analogous to entropy theory for scalar conservation laws such as u t + uu x = 0, which were developed by Oleinik and Kruzhkov (in x ∊ ℝ N ) in the 1950s–1960s. The Rosenau-Hyman K(2, 2) (compacton) equation
which has a special importance for applications, is studied. Compactons as compactly supported travelling wave solutions are shown to be δ-entropy. Shock and rarefaction waves are discussed for other NDEs such as
. This article was submitted by the author in English. Dedicated to the memory of Professors O.A. Oleinik and S.N. Kruzhkov  相似文献   

4.
The paper considers solutions of the coercive inequalities
defined on an arbitrary (possibly, unbounded) subset ℝ n , where n ≥ 2, L and are elliptic operators of the form
, and F is a certain function. __________ Translated from Sovremennaya Matematika. Fundamental'nye Napravleniya (Contemporary Mathematics. Fundamental Directions), Vol. 7, Partial Differential Equations, 2004.  相似文献   

5.
Let f(z) be a holomorphic Hecke eigenform of weight k with respect to SL(2, ) and let
denote the symmetric square L-function of f. A Voronoi type formula for
and the relation
are proved. Heuristic approaches to estimation of exponential sums arising in this connection are considered. Bibliography: 9 titles. __________ Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 314, 2004, pp. 247–256.  相似文献   

6.
Oscillatory and asymptotic behaviour of solutions of a class of fourth order nonlinear neutral difference equations of the form
and
are studied under the assumption < ∞, for different ranges of p(n). Sufficient conditions are obtained for the existence of positive bounded solutions of (E).   相似文献   

7.
In this paper, we establish sufficient conditions to guarantee the existence of at least three or 2n − 1 positive solutions of nonlocal boundary value problems consisting of the second-order differential equation with p-Laplacian
((1))
and one of following boundary conditions
((2))
and
((3))
Examples are presented to illustrate the main results. Supported by National Natural Science Foundation of P. R. China (No: 10371006).  相似文献   

8.
Let G be a multigraph. The star number s(G) of G is the minimum number of stars needed to decompose the edges of G. The star arboricity sa(G) of G is the minimum number of star forests needed to decompose the edges of G. As usual λK n denote the λ-fold complete graph on n vertices (i.e., the multigraph on n vertices such that there are λ edges between every pair of vertices). In this paper, we prove that for n ⩾ 2
((1))
((2))
  相似文献   

9.
Hua’s theorem with nine almost equal prime variables   总被引:2,自引:1,他引:1  
We sharpen Hua’s result by proving that each sufficiently large odd integer N can be written as
, where p j are primes. This result is as good as what was previously derived from the Generalized Riemann Hypothesis.   相似文献   

10.
We study the q-Clifford algebras
, called FRT–Clifford algebras, introduced by Faddeev, Reshetikhin and Takhtajan. It is shown that
acts on the q-exterior algebra
. Moreover, explicit formulas for the embedding of
into
and its relation to the vector and spin representations of
are given and proved.  相似文献   

11.
Let be a C*-algebra and X a Hilbert C* -module. If is a projection, let be the p-sphere of X. For φ a state of with support p in and consider the modular vector state φx of given by The spheres provide fibrations
and
These fibrations enable us to examine the homotopy type of the sets of modular vector states, and relate it to the homotopy type of unitary groups and spaces of projections. We regard modular vector states as generalizations of pure states to the context of Hilbert C*-modules, and the above fibrations as generalizations of the projective fibration of a Hilbert space.  相似文献   

12.
In this work we prove a new strong convergence result of the regularized successive approximation method given by yn+1 = qnz0 + (1 - qn)T^nyn, n = 1, 2,…,where lim n→∞ qn = 0 and ∞∑n=1 qn=∞ for T a total asymptotically nonexpansive mapping, i.e., T is such that
││T^n x - T^n y││ ≤ x - y ││ + kn^(1)φ(││x - y││) + kn^(2),where kn^1 and kn^2 are real null convergent sequences and φ:R^+→R^+ is continuous such that φ(0)=0 and limt→∞φ(t)/t≤ C for a certain constant C 〉 0.
Among other features, our results essentially generalize existing results on strong convergence for T nonexpansive and asymptotically nonexpansive. The convergence and stability analysis is given for both self- and nonself-mappings.  相似文献   

13.
Let R be a (not necessarily local) Noetherian ring and M a finitely generated R-module of finite dimension d. Let be an ideal of R and denote the intersection of all prime ideals . It is shown that
where for an Artinian R-module A we put A. As a consequence, it is proved that for all ideals of R, there are only finitely many non-isomorphic top local cohomology modules having the same support. In addition, we establish an analogue of the Lichtenbaum-Hartshorne vanishing theorem over rings that need not be local.  相似文献   

14.
Let u=u(x,t,uo)represent the global solution of the initial value problem for the one-dimensional fluid dynamics equation ut-εuxxt+δux+γHuxx+βuxxx+f(u)x=αuxx,u(x,0)=uo(x), whereα〉0,β〉0,γ〉0,δ〉0 andε〉0 are constants.This equation may be viewed as a one-dimensional reduction of n-dimensional incompressible Navier-Stokes equations. The nonlinear function satisfies the conditions f(0)=0,|f(u)|→∞as |u|→∞,and f∈C^1(R),and there exist the following limits Lo=lim sup/u→o f(u)/u^3 and L∞=lim sup/u→∞ f(u)/u^5 Suppose that the initial function u0∈L^I(R)∩H^2(R).By using energy estimates,Fourier transform,Plancherel's identity,upper limit estimate,lower limit estimate and the results of the linear problem vt-εv(xxt)+δvx+γHv(xx)+βv(xxx)=αv(xx),v(x,0)=vo(x), the author justifies the following limits(with sharp rates of decay) lim t→∞[(1+t)^(m+1/2)∫|uxm(x,t)|^2dx]=1/2π(π/2α)^(1/2)m!!/(4α)^m[∫R uo(x)dx]^2, if∫R uo(x)dx≠0, where 0!!=1,1!!=1 and m!!=1·3…(2m-3)…(2m-1).Moreover lim t→∞[(1+t)^(m+3/2)∫R|uxm(x,t)|^2dx]=1/2π(x/2α)^(1/2)(m+1)!!/(4α)^(m+1)[∫Rρo(x)dx]^2, if the initial function uo(x)=ρo′(x),for some functionρo∈C^1(R)∩L^1(R)and∫Rρo(x)dx≠0.  相似文献   

15.
By using the averaging technique, we establish some oscillation theorems for the second order damped elliptic differential equation N↑∑↓i,j=1 Di[AIY(x)Djy]+N↑∑↓i=1 bi(x)Diy+c(x)f(y)=0 which extend and improve some known results in the literature.  相似文献   

16.
Weighted composition operators from Bergman-type spaces into Bloch spaces   总被引:3,自引:0,他引:3  
Let ϕ be an analytic self-map and u be a fixed analytic function on the open unit disk D in the complex plane ℂ. The weighted composition operator is defined by
Weighted composition operators from Bergman-type spaces into Bloch spaces and little Bloch spaces are characterized by function theoretic properties of their inducing maps.  相似文献   

17.
On sums of a prime and four prime squares in short intervals   总被引:1,自引:1,他引:0  
In this paper, we prove that each sufficiently large integer N ≠1(mod 3) can be written as N=p+p1^2+p2^2+p3^2+p4^2, with
|p-N/5|≤U,|pj-√N/5|≤U,j=1,2,3,4,
where U=N^2/20+c and p,pj are primes.  相似文献   

18.
In this paper, sufficient conditions have been obtained under which every solution of
, oscillates or tends to zero or to ±∞ → ∞. Usually these conditions are stronger than
. An example is given to show that the condition (*) is not enough to arrive at the above conclusion. Existence of a positive (or negative) solution of
is considered.  相似文献   

19.
Let the coordinatex=(x 0,x 1,x 2,x 3) of the Minkowski spaceM 4 be arranged into a matrix
Then the Minkowski metric can be written as
. Imbed the space of 2 × 2 Hermitian matrices into the complex Grassmann manifoldF(2,2), the space of complex 4-planes passing through the origin ofC 2×4. The closure ofM 4 inF(2,2) is the compactification ofM 4. It is known that the conformal group acts on . It has already been proved that onF(2,2) there is anSu(2)-connection
whereZ is a 2 × 2 complex matrix andZ the complex conjugate and transposed matrix ofZ. Restrict this connection to
which is anSu(2)-connection on . It is proved that its curvature form
satisfies the Yang-Mills equation
. Project partially supported by the National Natural Science Foundation of China (Grant No. 19131010) and Fundamental Research Bureau of CAS.  相似文献   

20.
Letv(n) be the number of positive numbers up to a large limit n that are expressible in essentially more than one way by a binary formf that is a product ofl > 2 distinct linear factors with integral coefficients. We prove that
, where
, thus demonstrating in particular that it is exceptional for a number represented byf to have essentially more than one representation.  相似文献   

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