共查询到20条相似文献,搜索用时 31 毫秒
1.
Hiroaki Aikawa 《Proceedings of the American Mathematical Society》1997,125(1):229-234
Let be a bounded domain in , , and let . We consider positive functions on such that for all bounded harmonic functions on . We determine Lipschitz domains having such with .
2.
Let be the moduli space of based (anti-self-dual) instantons on of charge and rank . There is a natural inclusion . We show that the direct limit space is homotopy equivalent to . Let be a line in the complex projective plane and let be the blow-up at a point away from . can be alternatively described as the moduli space of rank holomorphic bundles on with and and with a fixed holomorphic trivialization on .
3.
Yann Bugeaud 《Proceedings of the American Mathematical Society》1997,125(11):3203-3208
One of the purposes of this note is to correct the proof of a recent result of Y. Guo & M. Le on the equation . Moreover, we prove that the diophantine equation , , , , , gcd, , has only finitely many solutions, all of which satisfying .
4.
Gabriel Navarro Wolfgang Willems 《Proceedings of the American Mathematical Society》1997,125(6):1589-1591
Let and be distinct prime numbers and let be a finite group. If is a -block of and is a -block, we study when the set of ordinary irreducible characters in the blocks and coincide.
5.
Yuan Xu 《Proceedings of the American Mathematical Society》1997,125(10):2963-2973
Let be the intertwining operator with respect to the reflection invariant measure on the unit sphere in Dunkl's theory on spherical -harmonics associated with reflection groups. Although a closed form of is unknown in general, we prove that
where is the unit ball of and is a constant. The result is used to show that the expansion of a continuous function as Fourier series in -harmonics with respect to is uniformly Cesáro summable on the sphere if , provided that the intertwining operator is positive.
6.
Dave Witte 《Proceedings of the American Mathematical Society》1997,125(11):3433-3438
Let be a discrete subgroup of a simply connected, solvable Lie group , such that has the same Zariski closure as . If is any finite-dimensional representation of , we show that virtually extends to a continuous representation of . Furthermore, the image of is contained in the Zariski closure of the image of . When is not discrete, the same conclusions are true if we make the additional assumption that the closure of is a finite-index subgroup of (and is closed and is continuous).
7.
Katsuro Sakai 《Proceedings of the American Mathematical Society》1997,125(9):2809-2813
Let be the -dimensional universal Menger compactum, a -set in and a metrizable zero-dimensional compact group with the unit. It is proved that there exists a semi-free -action on such that is the fixed point set of every . As a corollary, it follows that each compactum with can be embedded in as the fixed point set of some semi-free -action on .
8.
Nancy Hingston 《Proceedings of the American Mathematical Society》1997,125(10):3099-3106
Let be an isolated closed geodesic of length on a compact Riemannian manifold which is homologically visible in the dimension of its index, and for which the index of the iterates has the maximal possible growth rate. We show that has a sequence , , of prime closed geodesics of length where and . The hypotheses hold in particular when is a two-sphere and the ``shortest' Lusternik-Schnirelmann closed geodesic is isolated and ``nonrotating'.
9.
Jungkai Alfred Chen 《Proceedings of the American Mathematical Society》1997,125(8):2221-2225
We prove that for any smooth projective variety of dimension , there exists an integer , such that for any integer , there exists a smooth curve in with .
10.
Changyu Xia 《Proceedings of the American Mathematical Society》1997,125(6):1801-1806
Let be an ()-dimensional compact Riemannian manifold with nonnegative Ricci curvature and nonempty boundary . Assume that the principal curvatures of are bounded from below by a positive constant . In this paper, we prove that the first nonzero eigenvalue of the Laplacian of acting on functions on satisfies with equality holding if and only if is isometric to an -dimensional Euclidean ball of radius . Some related rigidity theorems for are also proved.
11.
We consider examples of rank one perturbations with a cyclic vector for . We prove that for any bounded measurable set , an interval, there exist so that
eigenvalue agrees with up to sets of Lebesgue measure zero. We also show that there exist examples where has a.c. spectrum for all , and for sets of 's of positive Lebesgue measure, also has point spectrum in , and for a set of 's of positive Lebesgue measure, also has singular continuous spectrum in .
eigenvalue agrees with up to sets of Lebesgue measure zero. We also show that there exist examples where has a.c. spectrum for all , and for sets of 's of positive Lebesgue measure, also has point spectrum in , and for a set of 's of positive Lebesgue measure, also has singular continuous spectrum in .
12.
Peter Semrl 《Proceedings of the American Mathematical Society》1997,125(9):2677-2680
Let be an algebra. A mapping is called a -local automorphism if for every there is an automorphism , depending on and , such that and (no linearity, surjectivity or continuity of is assumed). Let be an infinite-dimensional separable Hilbert space, and let be the algebra of all linear bounded operators on . Then every -local automorphism is an automorphism. An analogous result is obtained for derivations.
13.
Barry Simon 《Proceedings of the American Mathematical Society》1997,125(1):203-208
Given any sequence of positive energies and any monotone function on with , , we can find a potential on such that are eigenvalues of and .
14.
Raú l E. Curto Carlos Herná ndez G. 《Proceedings of the American Mathematical Society》1997,125(11):3299-3301
We prove that a C-algebra is prime iff for every where denotes Taylor spectrum and are the left and right multiplication operators acting on
15.
Yong Ding 《Proceedings of the American Mathematical Society》1997,125(10):2939-2942
In this note we show that and the fractional integral and maximal operators with rough kernel respectively, are bounded operators from to where and
16.
On the von Neumann-Jordan constant for Banach spaces 总被引:2,自引:0,他引:2
Let be the von Neumann-Jordan constant for a Banach space . It is known that for any Banach space ; and is a Hilbert space if and only if . We show that: (i) If is uniformly convex, is less than two; and conversely the condition implies that admits an equivalent uniformly convex norm. Hence, denoting by the infimum of all von Neumann-Jordan constants for equivalent norms of , is super-reflexive if and only if . (ii) If , (the same value as that of -space), is of Rademacher type and cotype for any with , where ; the converse holds if is a Banach lattice and is finitely representable in or .
17.
Michael Rosen 《Proceedings of the American Mathematical Society》1997,125(5):1299-1303
Let be a finite field, , and . Let be the field extension of obtained by adjoining the -torsion on the Carlitz module. The class number of can be written as a product . The number is called the relative class number. In this paper a formula for is derived which is the analogue of the Maillet determinant formula for the relative class number of the cyclotomic field of -th roots of unity. Some consequences of this formula are also derived.
18.
Olivier Courcelle Jean-Marc Gambaudo Charles Tresser 《Proceedings of the American Mathematical Society》1997,125(10):3051-3058
Consider an orientation preserving homeomorphism of the 2-disk with an infinite set of nested periodic orbits , such that, for all , the restriction of to the complement of the first orbits, from to , is times reducible in the sense of Nielsen and Thurston. We define combinatorial renormalization operators for such maps, and study the fixed points of these operators. We also recall the corresponding theory for endomorphisms of the interval, and give elements of comparison of the theories in one and two dimensions.
19.
Jü rgen Herzog Takayuki Hibi 《Proceedings of the American Mathematical Society》1997,125(6):1579-1583
Here we study the maximal dimension of the annihilator ideals
of artinian graded rings with a given Hilbert function, where is the polynomial ring in the variables over a field with each , is a graded ideal of , and is the graded maximal ideal of . As an application to combinatorics, we introduce the notion of -facets and obtain some informations on the number of -facets of simplicial complexes with a given -vector.
of artinian graded rings with a given Hilbert function, where is the polynomial ring in the variables over a field with each , is a graded ideal of , and is the graded maximal ideal of . As an application to combinatorics, we introduce the notion of -facets and obtain some informations on the number of -facets of simplicial complexes with a given -vector.
20.
Erdos and Szemerédi conjectured that if is a set of positive integers, then there must be at least integers that can be written as the sum or product of two elements of . Erdos and Szemerédi proved that this number must be at least for some and . In this paper it is proved that the result holds for .