共查询到20条相似文献,搜索用时 15 毫秒
1.
A new interesting topology on graphs of partial maps is introduced. This topology can be considered as a natural extension to a non locally compact
setting of former topologies defined by P. Brandi, R. Ceppitelli and K. Back, having applications in mathematical economics,
differential equations and in the convergence of dynamic programming models. New characterizations of boundedly Atsuji spaces
are given by the coincidence of and the topology τ
ucb
of uniform convergence on bounded sets on C(X,Y) and by topological properties of .
相似文献
2.
Luigi Ambrosio Estibalitz Durand-Cartagena 《Rendiconti del Circolo Matematico di Palermo》2009,58(1):1-10
This note is devoted to the differentiability properties of -Lipschitz maps defined on abstract Wiener spaces and with values in metric spaces (Y,d
Y
). We prove the existence γ-a.e. of local seminorms in the Cameron-Martin space which allow to compute the metric derivative of the map.
Second Author partially supported by DGES (Spain) MTM2006-03531. 相似文献
3.
Nic Koban 《Geometriae Dedicata》2007,124(1):133-141
We compute the geometric invariants of a product G × H of groups in terms of and . This gives a sufficient condition in terms of and for a normal subgroup of G × H with abelian quotient to be of type F
n
. We give an example involving the direct product of the Baumslag–Solitar group BS1,2 with itself.
相似文献
4.
This work is concerned with the fast diffusion equation , where 0 < m < 1 and κ < 1. A global positive solution is said to quench regularly in infinite time if for some bounded sequence and some , and if for all compact . It is shown that such regular quenching in infinite time occurs for a large class of initial data if κ > m , whereas it is impossible in one space dimension when κ < −m and the solution is radially symmetric and nondecreasing for x > 0.
相似文献
5.
We study the null solutions of iterated applications of the spherical (Atiyah-Singer) Dirac operator on locally defined polynomial forms on the unit sphere of ; functions valued in the universal Clifford algebra , here called spherical k-regular functions. We construct the kernel functions, get the integral representation formula and Cauchy integral formula
of spherical k-regular functions, and as applications, the weak solutions of higher order inhomogeneous spherical (Atiyah-Singer) Dirac
equations . We obtain, in particular, the weak solution of an inhomogeneous spherical Poisson equation Δ
s
g = f.
This work was partially supported by NNSF of China (No.10471107) and RFDP of Higher Education (No.20060486001). 相似文献
6.
Given two vectors x, y in a Hilbert space and a weakly closed -module , we provide a necessary and sufficient condition for the existence of a compact operator T in satisfying Tx = y. 相似文献
7.
A set of positive integers is a perfect difference set if every nonzero integer has a unique representation as the difference of two elements of . We construct dense perfect difference sets from dense Sidon sets. As a consequence of this new approach we prove that there exists a perfect difference set such that
.
Also we prove that there exists a perfect difference set
such that
A(x)/≥ 1/.
The work of J. C. was supported by Grant MTM 2005-04730 of MYCIT (Spain).
The work of M. B. N. was supported in part by grants from the NSA Mathematical Sciences Program and the PSC-CUNY Research
Award Program. 相似文献
8.
Peer Christian Kunstmann 《Archiv der Mathematik》2008,91(2):178-186
We consider the Stokes operator A on unbounded domains of uniform C
1,1-type. Recently, it has been shown by Farwig, Kozono and Sohr that – A generates an analytic semigroup in the spaces , 1 < q < ∞, where for q ≥ 2 and for q ∈ (1, 2). Moreover, it was shown that A has maximal L
p
-regularity in these spaces for p ∈ (1,∞). In this paper we show that ɛ + A has a bounded H
∞-calculus in for all q ∈ (1, ∞) and ɛ > 0. This allows to identify domains of fractional powers of the Stokes operator.
Received: 12 October 2007 相似文献
9.
Thomas Krainer 《Annals of Global Analysis and Geometry》2009,35(4):345-361
Let A be an elliptic operator on a compact manifold with boundary , and let be a covering map, where Y is a closed manifold. Let A
C
be a realization of A subject to a coupling condition C that is elliptic with parameter in the sector Λ. By a coupling condition we mean a nonlocal boundary condition that respects
the covering structure of the boundary. We prove that the resolvent trace for N sufficiently large has a complete asymptotic expansion as . In particular, the heat trace has a complete asymptotic expansion as , and the -function has a meromorphic extension to .
相似文献
10.
A contact-stationary Legendrian submanifold of is a Legendrian submanifold whose volume is stationary under contact deformations. The simplest contact-stationary Legendrian
submanifold (actually minimal Legendrian) is the real, equatorial n-sphere S
0. This paper develops a method for constructing contact-stationary (but not minimal) Legendrian submanifolds of by gluing together configurations of sufficiently many many U(n + 1)-rotated copies of S
0. Two examples of the construction, corresponding to finite cyclic subgroups of U(n + 1) are given. The resulting submanifolds
are very symmetric; are geometrically akin to a ‘necklace’ of copies of S
0 attached to each other by narrow necks and winding a large number of times around before closing up on themselves; and are topologically equivalent to . 相似文献
11.
Given a metric space X and a Banach space (E, ||·||) we use an index of σ-fragmentability for maps to estimate the distance of f to the space B
1(X, E) of Baire one functions from X into (E, ||·||). When X is Polish we use our estimations for these distances to give a quantitative version of the well known Rosenthal’s result
stating that in the pointwise relatively countably compact sets are pointwise relatively compact. We also obtain a quantitative version of
a Srivatsa’s result that states that whenever X is metric any weakly continuous function belongs to B
1(X, E): our result here says that for an arbitrary we have
where osc stands for the supremum of the oscillations of at all points . As a consequence of the above we prove that for functions in two variables , X complete metric and K compact, there exists a G
δ-dense set such that the oscillation of f at each is bounded by the oscillations of the partial functions f
x
and f
k
. A representative result in this direction, that we prove using games, is the following: if X is a σ–β-unfavorable space and K is a compact space, then there exists a dense G
δ-subset D of X such that, for each ,
When the right hand side of the above inequality is zero we are dealing with separately continuous functions and we obtain as a particular case some well-known results obtained by the third named author in the mid 1970s.
C. Angosto, B. Cascales and I. Namioka are supported by the Spanish grants MTM2005-08379 (MEC & FEDER) and 00690/PI/04 (Fund.
Séneca). C. Angosto is also supported by the FPU grant AP2003-4443 (MEC & FEDER). 相似文献
12.
Bing Ye Wu 《Annals of Global Analysis and Geometry》2007,31(4):375-384
Let
be a Minkowski 3-space of Randers type with
, where
is the Euclidean metric and
. We consider minimal surfaces in
and prove that if a connected surface M in
is minimal with respect to both the Busemann–Hausdorff volume form and the Holmes–Thompson volume form, then up to a parallel
translation of
, M is either a piece of plane or a piece of helicoid which is generated by lines screwing about the x
3-axis.
相似文献
13.
Jin Han Park Jong Seo Park Young Chel Kwun 《Fuzzy Optimization and Decision Making》2008,7(4):305-315
In this paper, we give some common fixed point theorems for five mappings satisfying some conditions in -fuzzy metric spaces. 相似文献
14.
Tomas Ya. Azizov Jussi Behrndt Peter Jonas Carsten Trunk 《Integral Equations and Operator Theory》2009,63(2):151-163
For closed linear operators or relations A and B acting between Hilbert spaces and the concepts of compact and finite rank perturbations are defined with the help of the orthogonal projections P
A
and P
B
in onto the graphs of A and B. Various equivalent characterizations for such perturbations are proved and it is shown that these notions are a natural
generalization of the usual concepts of compact and finite rank perturbations.
Sadly, our colleague and friend Peter Jonas passed away on July, 18th 2007. 相似文献
15.
Vasily A. Prokhorov Edward B. Saff Maxim Yattselev 《Complex Analysis and Operator Theory》2009,3(2):501-524
Let be a bounded simply connected domain with boundary Γ and let be a regular compact set with connected complement. In this paper we investigate asymptotics of the extremal constants:
where is the supremum norm on a compact set K, is the set of all algebraic polynomials of degree at most m, and as . Subsequently, we obtain asymptotic behavior of the Kolmogorov k-widths, , of the unit ball An∞ of restricted to E in C(E), where H∞ is the Hardy space of bounded analytic functions on G and C(E) is the space of continuous functions on E.
Received: April 24, 2008. Accepted: May 15, 2008. 相似文献
16.
The Segre variety in PG(5, 2) is a 21-set of points which is shown to have a cubic equation Q(x) = 0. If T(x, y, z) denotes the alternating trilinear form obtained by completely polarizing the cubic polynomial Q, then the associate
U
# of an r-flat is defined to be
and so is an s-flat for some s. Those lines L of PG(5, 2) which are singular, satisfying that is L
# = PG(5.2), are shown to form a complete spread of 21 lines. For each r-flat its associate U
# is determined. Examples are given of four kinds of planes P which are self-associate, P
# = P, and three kinds of planes for which P, P
#, P
## are disjoint planes such that P
### = P.
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17.
Complementing the results of (Lotta and Nacinovich, Adv. Math. 191(1): 114–146, 2005), we show that the minimal orbit M of a real form G of a semisimple complex Lie group in a flag manifold is CR-symmetric (see (Kaup and Zaitsev Adv. Math. 149(2):145–181, 2000)) if and only if the corresponding CR algebra admits a gradation compatible with the CR structure.
相似文献
18.
Ameer Athavale 《Complex Analysis and Operator Theory》2008,2(3):417-428
Let be a strictly pseudoconvex bounded domain in with C
2 boundary . If a subnormal m-tuple T of Hilbert space operators has the spectral measure of its minimal normal extension N supported on , then T is referred to as a -isometry. Using some non-trivial approximation theorems in the theory of several complex variables, we establish a commutant
lifting theorem for those -isometries whose (joint) Taylor spectra are contained in a special superdomain Ω of . Further, we provide a function-theoretic characterization of those subnormal tuples whose Taylor spectra are contained in
Ω and that are quasisimilar to a certain (fixed) -isometry T (of which the multiplication tuple on the Hardy space of the unit ball in is a rather special example).
Submitted: September 9, 2007. Revised: October 10, 2007. Accepted: October 24, 2007. 相似文献
19.
Let be open, let be the Dirac operator in and let be the Clifford algebra constructed over the quadratic space . If for fixed, denotes the space of r-vectors in , then an -valued smooth function W = W
r
+ W
r+2 in Ω is said to satisfy the Moisil-Théodoresco system if . In terms of differential forms, this means that the corresponding - valued smooth form w = w
r
+ w
r+2 satisfies in Ω the system d
*
w
r
= 0, dw
r
+ d
*
w
r+2 = 0; dw
r+2 = 0.
Based on techniques and results concerning conjugate harmonic functions in the framework of Clifford analysis, a structure
theorem is proved for the solutions of the Moisil-Théodoresco system.
相似文献
20.
This paper concerns variational inclusions of the form where f is a single locally Lipschitz subanalytic function and F is a set-valued map acting in Banach spaces. We prove the existence and the convergence of a sequence (x
k
) satisfying where lies to which is the Clarke Jacobian of f at the point x
k
.
相似文献