共查询到20条相似文献,搜索用时 78 毫秒
1.
Positivity - Let X and Y be locally compact Hausdorff spaces. In this paper we study surjections $$T: A \longrightarrow B$$ between certain subsets A and B of $$C_0(X)$$ and $$C_0(Y)$$ ,... 相似文献
2.
Functional Analysis and Its Applications - In this note we discuss some necessary and some sufficient conditions for the relative injectivity of the $$C_0(S)$$ -module $$C_0(S)$$ , where $$S$$ is a... 相似文献
3.
Qian Jin Luo 《数学学报(英文版)》2020,36(6):711-722
Let B be the unit disc in R~2, H be the completion of C_0∞(B) under the norm■ .By the method of blow-up analysis and an argument of rearrangement with respect to the standard hyperbolic metric ■, we prove that, for any fixed■ ,the supremum■ .This is an analog of early results of Lu–Yang(Discrete Contin. Dyn. Syst., 2009) and Yang(Trans.Amer. Math. Soc., 2007), and extends those of Wang–Ye(Adv. Math., 2012) and Yang–Zhu(Ann.Global Anal. Geom., 2016). 相似文献
4.
Balister Paul Bollobás Béla Lee Jonathan D. Morris Robert Riordan Oliver 《Archiv der Mathematik》2019,112(4):371-375
Archiv der Mathematik - We present a short and purely combinatorial proof of Linnik’s theorem: for any $$\varepsilon >0$$ there exists a constant $$C_\varepsilon $$ such that for any... 相似文献
5.
Monatshefte für Mathematik - This paper concerns the spectrum and the fine spectrum of the discrete generalized Cesàro operator $$C_{t}$$ , where $$0\le t<1$$ , on Banach sequence... 相似文献
6.
Archiv der Mathematik - The space of unitary $$C_{0}$$ -semigroups on a separable infinite-dimensional Hilbert space, when viewed under the topology of uniform weak operator convergence on compact... 相似文献
7.
Semigroup Forum - By using the method of functional analysis, especially $$C_0$$ -semigroup theory and spectral theory of linear operators we prove the well-posedness and the existence of a unique... 相似文献
8.
We show that if A is a separable, nuclear,
-absorbing (or strongly purely infinite) C*-algebra which is homotopic to zero in an ideal-system preserving way, then A is the inductive limit of C*-algebras of the form
where Γ is a finite connected graph (and
is the algebra of continuous functions on Γ that vanish at a distinguished point
).We show further that if B is any separable, nuclear C*-algebra, then
is isomorphic to a crossed product
where D is an inductive limit of C*-algebras of the form
(and D is
-absorbing and homotopic to zero in an ideal-system preserving way).Received: December 2003 Revision: July 2004 Accepted: July 2004 相似文献
9.
Laketa Petra N. Nastić Aleksandar S. Ristić Miroslav M. 《Mediterranean Journal of Mathematics》2018,15(1):1-14
Mediterranean Journal of Mathematics - Let $$C_{\varphi }$$ be the composition operator with monomial symbol $$\varphi (z)=z^m$$ , $$z\in \mathbb {D}$$ , for some positive integer m. In this... 相似文献
10.
We study sums of bisectorial operators on a Banach space X and show that interpolation spaces between X and D(A) (resp. D(B)) are maximal regularity spaces for the problem Ay + By = x in X. This is applied to the study of regularity properties of the evolution equation u′ + Au = f on
for
or
and the evolution equation u′ + Au = f on [0, 2π] with periodic boundary condition u(0) = u(2π) in
or
相似文献
11.
Doklady Mathematics - An adequate local metric characteristic is introduced for level sets of $$C_{H}^{1}$$ -mappings of Carnot manifolds to Carnot–Carathéodory spaces. Moreover, for... 相似文献
12.
Dana D. Clahane 《Integral Equations and Operator Theory》2005,51(1):41-56
Let H2(D) denote the Hardy space of a bounded symmetric domain
in its standard Harish-Chandra realization, and let
be the weighted Bergman space with
and
where
is a critical value depending on D. Suppose that
is holomorphic. We show that if the composition operator
defined by
is compact (or, more generally, power-compact) on H2(D) or
then has a unique fixed point z0 in D. We then prove that the spectrum of
as an operator on these function spaces is precisely the set consisting of 0, 1, and all possible products of eigenvalues of
These results extend previous work by Caughran/Schwartz and MacCluer. As a corollary, we now have that MacCluers previous spectrum results on the unit ball Bn extend to Hp(n) (not only for p = 2 but for all p > 1) and
(for p 1), where n is the polydisk in
相似文献
13.
Miroslav Pavlović 《Mathematische Zeitschrift》2008,258(1):81-86
We prove that maps into
if and only if belongs to . In the case β < 1, we give another two equivalent conditions.
Supported by MNZŽS Serbia, Project No. ON144010. 相似文献
14.
Mathematical Programming - For two integers $$k>0$$ and $$\ell $$ , a graph $$G=(V,E)$$ is called $$(k,\ell )$$ -tight if $$|E|=k|V|-\ell $$ and $$i_G(X)\le k|X|-\ell $$ for each... 相似文献
15.
Periodic Solutions of Third-order Differential Equations with Finite Delay in Vector-valued Functional Spaces
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In this paper, we study the well-posedness of the third-order differential equation with finite delay(P_3): αu'"(t) + u"(t) = Au(t) + Bu'(t) + Fut +f(t)(t ∈ T := [0,2π]) with periodic boundary conditions u(0) = u(2π), u'(0) = u"(2π),u"(0)=u"(2π) in periodic Lebesgue-Bochner spaces Lp(T;X) and periodic Besov spaces B_(p,q)~s(T;X), where A and B are closed linear operators on a Banach space X satisfying D(A) ∩ D(B) ≠ {0}, α≠ 0 is a fixed constant and F is a bounded linear operator from Lp([-2π, 0]; X)(resp. Bp,qs([-2π, 0]; X)) into X, ut is given by ut(s) = u(t + s) when s ∈ [-2π,0]. Necessary and sufficient conditions for the Lp-well-posedness(resp. B_(p,q)~s-well-posedness)of(P_3) are given in the above two function spaces. We also give concrete examples that our abstract results may be applied. 相似文献
16.
The weak tightness wt(X) of a space X was introduced in Carlson (Topol Appl 249:103–111, 2018) with the property $$wt(X)\le t(X)$$. We investigate several well-known results concerning t(X) and consider whether they extend to the weak tightness setting. First we give an example of a non-sequential compactum X such that $$wt(X)=\aleph _0<t(X)$$ under $$2^{\aleph _0}=2^{\aleph _1}$$. In particular, this demonstrates the celebrated Balogh’s (Proc Am Math Soc 105(3):755–764, 1989) Theorem does not hold in general if countably tight is replaced with weakly countably tight. Second, we introduce the notion of an S-free sequence and show that if X is a homogeneous compactum then $$|X|\le 2^{wt(X)\pi \chi (X)}$$. This refines a theorem of de la Vega (Topol Appl 153:2118–2123, 2006). In the case where the cardinal invariants involved are countable, this also represents a variation of a theorem of Juhász and van Mill (Proc Am Math Soc 146(1):429–437, 2018). In this connection we also show $$w(X)\le 2^{wt(X)}$$ for a homogeneous compactum. Third, we show that if X is a $$T_1$$ space, $$wt(X)\le \kappa $$, X is $$\kappa ^+$$-compact, and $$\psi (\overline{D},X)\le 2^\kappa $$ for any $$D\subseteq X$$ satisfying $$|D|\le 2^\kappa $$, then (a) $$d(X)\le 2^\kappa $$ and (b) X has at most $$2^\kappa $$-many $$G_\kappa $$-points. This is a variation of another theorem of Balogh (Topol Proc 27:9–14, 2003). Finally, we show that if X is a regular space, $$\kappa =L(X)wt(X)$$, and $$\lambda $$ is a caliber of X satisfying $$\kappa <\lambda \le \left( 2^{\kappa }\right) ^+$$, then $$d(X)\le 2^{\kappa }$$. This extends of theorem of Arhangel$$'$$skiĭ (Topol Appl 104:13–26, 2000). 相似文献
17.
Haïkel Skhiri 《Integral Equations and Operator Theory》2008,62(1):137-148
Let be the algebra of all bounded linear operators on a complex Banach space X and γ(T) be the reduced minimum modulus of operator . In this work, we prove that if , is a surjective linear map such that is an invertible operator, then , for every , if and only if, either there exist two bijective isometries and such that for every , or there exist two bijective isometries and such that for every . This generalizes for a Banach space the Mbekhta’s theorem [12].
相似文献
18.
Let X be a compact convex set and let ext X stand for the set of extreme points of X. We show that if $$f:X\rightarrow {\mathbb {R}}$$ is an affine function with the point of continuity property such that $$f\le 0$$ on $${\text {ext}}\,X$$, then $$f\le 0$$ on X. As a corollary of this minimum principle, we obtain a generalization of a theorem by C.H. Chu and H.B. Cohen by proving the following result. Let X, Y be compact convex sets such that every extreme point of X and Y is a weak peak point and let $$T:\mathfrak {A}^c(X)\rightarrow \mathfrak {A}^c(Y)$$ be an isomorphism such that $$\left\| T\right\| \cdot \left\| T^{-1}\right\| <2$$. Then $${\text {ext}}\,X$$ is homeomorphic to $${\text {ext}}\,Y$$. 相似文献
19.
Henri Heinich 《Journal of Theoretical Probability》2006,19(2):509-534
In this paper, we generalize the Kantorovich functional to K?the-spaces for a cost or a profit function. We examine the convergence
of probabilities with respect to this functional for some K?the-spaces. We study the Monge problem: Let
be a K?the-space, P and Q two Borel probabilities defined on a Polish space M and a cost function
. A K?the functional
is defined by
(P, Q) = inf
where
is the law of X. If c is a profit function, we note
. (P, Q) = sup
Under some conditions, we show the existence of a Monge function, φ, such that
, or
.
相似文献
20.
Davar Khoshnevisan Narn-Rueih Shieh Yimin Xiao 《Probability Theory and Related Fields》2008,140(1-2):129-167
Let X
1, ..., X
N
denote N independent, symmetric Lévy processes on R
d
. The corresponding additive Lévy process is defined as the following N-parameter random field on R
d
:
Khoshnevisan and Xiao (Ann Probab 30(1):62–100, 2002) have found a necessary and sufficient condition for the zero-set of to be non-trivial with positive probability. They also provide bounds for the Hausdorff dimension of which hold with positive probability in the case that can be non-void.
Here we prove that the Hausdorff dimension of is a constant almost surely on the event . Moreover, we derive a formula for the said constant. This portion of our work extends the well known formulas of Horowitz
(Israel J Math 6:176–182, 1968) and Hawkes (J Lond Math Soc 8:517–525, 1974) both of which hold for one-parameter Lévy processes.
More generally, we prove that for every nonrandom Borel set F in (0,∞)
N
, the Hausdorff dimension of is a constant almost surely on the event . This constant is computed explicitly in many cases.
The research of N.-R. S. was supported by a grant from the Taiwan NSC. 相似文献