共查询到20条相似文献,搜索用时 31 毫秒
1.
Matt Greenwood Xiao-Song Lin 《Transactions of the American Mathematical Society》1999,351(9):3659-3672
We prove that the knot invariant induced by a -homology 3-sphere invariant of order in Ohtsuki's sense, where , is of order . The method developed in our computation shows that there is no -homology 3-sphere invariant of order 5.
2.
Naihuan Jing Kailash C. Misra 《Transactions of the American Mathematical Society》1999,351(4):1663-1690
We construct explicitly the -vertex operators (intertwining operators) for the level one modules of the classical quantum affine algebras of twisted types using interacting bosons, where for (), for , for (), and for (). A perfect crystal graph for is constructed as a by-product.
3.
Suppose that is left invertible in for all , where is an open subset of the complex plane. Then an operator-valued function is a left resolvent of in if and only if has an extension , the resolvent of which is a dilation of of a particular form. Generalized resolvents exist on every open set , with included in the regular domain of . This implies a formula for the maximal radius of regularity of in terms of the spectral radius of its generalized inverses. A solution to an open problem raised by
J. Zemánek is obtained.
J. Zemánek is obtained.
4.
Qingbo Huang 《Transactions of the American Mathematical Society》1999,351(5):2025-2054
In this paper we prove the Harnack inequality for nonnegative solutions of the linearized parabolic Monge-Ampère equation
on parabolic sections associated with , under the assumption that the Monge-Ampère measure generated by satisfies the doubling condition on sections and the uniform continuity condition with respect to Lebesgue measure. The theory established is invariant under the group , where denotes the group of all invertible affine transformations on .
5.
J. A. de la Peñ a M. Takane 《Transactions of the American Mathematical Society》1999,351(9):3857-3868
Let be a finite dimensional tame algebra over an algebraically closed field . It has been conjectured that any almost split sequence with indecomposable modules has and in case , then exactly one of the is a projective-injective module. In this work we show this conjecture in case all the are directing modules, that is, there are no cycles of non-zero, non-iso maps between indecomposable -modules. In case, and are isomorphic, we show that and give precise information on the structure of .
6.
F. Andreu J. M. Mazó n S. Segura de Leó n J. Toledo 《Transactions of the American Mathematical Society》1999,351(1):285-306
In this paper we study existence and uniqueness of solutions for the boundary-value problem, with initial datum in ,
where a is a Carathéodory function satisfying the classical Leray-Lions hypothesis, is the Neumann boundary operator associated to , the gradient of and is a maximal monotone graph in with .
7.
Tianxuan Miao 《Transactions of the American Mathematical Society》1999,351(11):4675-4692
For any locally compact group , let and be the Fourier and the Fourier-Stieltjes algebras of , respectively. is decomposed as a direct sum of and , where is a subspace of consisting of all elements that satisfy the property: for any and any compact subset , there is an with and such that is characterized by the following: an element is in if and only if, for any there is a compact subset such that for all with and . Note that we do not assume the amenability of . Consequently, we have for all if is noncompact. We will apply this characterization of to investigate the general properties of and we will see that is not a subalgebra of even for abelian locally compact groups. If is an amenable locally compact group, then is the subspace of consisting of all elements with the property that for any compact subset , .
8.
Donald G. James 《Transactions of the American Mathematical Society》1999,351(2):825-835
Let be a quadratic extension of a global field , of characteristic not two, and the integral closure in of a Dedekind ring of -integers in . Then is isomorphic to the spinorial kernel for an indefinite quadratic -lattice of rank 4. The isomorphism is used to study the conjugacy classes of unitary groups of primitive odd binary hermitian matrices under the action of .
9.
Maohua Le 《Transactions of the American Mathematical Society》1999,351(3):1063-1074
In this paper we prove that the equation , , , , , has only the solutions and with is a prime power. The proof depends on some new results concerning the upper bounds for the number of solutions of the generalized Ramanujan-Nagell equations.
10.
Hon-kit Wai 《Transactions of the American Mathematical Society》1999,351(6):2141-2182
Given an -invariant Morse function and an -invariant Riemannian metric , a family of finite dimensional subcomplexes , , of the Witten deformation of the -equivariant de Rham complex is constructed, by studying the asymptotic behavior of the spectrum of the corresponding Laplacian as . In fact the spectrum of can be separated into the small eigenvalues, finite eigenvalues and the large eigenvalues. Then one obtains as the complex of eigenforms corresponding to the small eigenvalues of . This permits us to verify the -equivariant Morse inequalities. Moreover suppose is self-indexing and satisfies the Morse-Smale condition, then it is shown that this family of subcomplexes converges as to a geometric complex which is induced by and calculates the -equivariant cohomology of .
11.
Andreas Seeger Stephen Wainger James Wright Sarah Ziesler 《Transactions of the American Mathematical Society》1999,351(9):3757-3769
This paper is concerned with singular convolution operators in , , with convolution kernels supported on radial surfaces . We show that if , then boundedness holds if and only if . This statement can be reduced to a similar statement about the multiplier in . We also construct smooth for which the corresponding operators are bounded for but unbounded for , for given . Finally we discuss some examples of singular integrals along convex curves in the plane, with odd extensions.
12.
Scrambled sets of continuous maps of 1-dimensional polyhedra 总被引:4,自引:0,他引:4
Jiehua Mai 《Transactions of the American Mathematical Society》1999,351(1):353-362
Let be a 1-dimensional simplicial complex in without isolated vertexes, be the polyhedron of with the metric induced by , and be a continuous map. In this paper we prove that if is finite, then the interior of every scrambled set of in is empty. We also show that if is an infinite complex, then there exist continuous maps from to itself having scrambled sets with nonempty interiors, and if or , then there exist maps of with the whole space being a scrambled set.
13.
Joyce Wagner 《Transactions of the American Mathematical Society》1999,351(1):41-62
Let be a self-map of a hyperbolic surface with boundary. The Nielsen number, , depends only on the induced map of the fundamental group, which can be viewed as a free group on generators, . We determine conditions for fixed points to be in the same fixed point class and if these conditions are enough to determine the fixed point classes, we say that is -characteristic. We define an algebraic condition on the and show that ``most' maps satisfy this condition and that all maps which satisfy this condition are -characteristic. If is -characteristic, we present an algorithm for calculating and prove that the inequality holds, where denotes the Lefschetz number of and the Euler characteristic of , thus answering in part a question of Jiang and Guo.
14.
Mohammed Moussaoui Alberto Seeger 《Transactions of the American Mathematical Society》1999,351(9):3687-3711
The purpose of this work is twofold: on the one hand, we study the second-order behaviour of a nonsmooth convex function defined over a reflexive Banach space . We establish several equivalent characterizations of the set , known as the second-order subdifferential of at relative to . On the other hand, we examine the case in which is the functional integral associated to a normal convex integrand . We extend a result of Chi Ngoc Do from the space to a possible nonreflexive Banach space . We also establish a formula for computing the second-order subdifferential .
15.
Exact Hausdorff measure and intervals of maximum density for Cantor sets 总被引:16,自引:0,他引:16
Elizabeth Ayer Robert S. Strichartz 《Transactions of the American Mathematical Society》1999,351(9):3725-3741
Consider a linear Cantor set , which is the attractor of a linear iterated function system (i.f.s.) , , on the line satisfying the open set condition (where the open set is an interval). It is known that has Hausdorff dimension given by the equation , and that is finite and positive, where denotes Hausdorff measure of dimension . We give an algorithm for computing exactly as the maximum of a finite set of elementary functions of the parameters of the i.f.s. When (or more generally, if and are commensurable), the algorithm also gives an interval that maximizes the density . The Hausdorff measure is not a continuous function of the i.f.s. parameters. We also show that given the contraction parameters , it is possible to choose the translation parameters in such a way that , so the maximum density is one. Most of the results presented here were discovered through computer experiments, but we give traditional mathematical proofs.
16.
Saharon Shelah Jö rg Brendle Saharon Shelah 《Transactions of the American Mathematical Society》1999,351(7):2643-2674
For a free ultrafilter on we study several cardinal characteristics which describe part of the combinatorial structure of . We provide various consistency results; e.g. we show how to force simultaneously many characters and many -characters. We also investigate two ideals on the Baire space naturally related to and calculate cardinal coefficients of these ideals in terms of cardinal characteristics of the underlying ultrafilter.
17.
Douglas L. Costa Gordon E. Keller 《Transactions of the American Mathematical Society》1999,351(12):5051-5088
We give a characterization theorem for the -normalized subgroups of , where is any commutative ring. This is the last of the simple Chevalley-Demazure group-schemes for which such a theorem is lacking.
18.
Xiaotie She 《Transactions of the American Mathematical Society》1999,351(3):1075-1094
Let be a normalised new form of weight for over and , its base change lift to . A sufficient condition is given for the nonvanishing at the center of the critical strip of infinitely many cubic twists of the -function of . There is an algorithm to check the condition for any given form. The new form of level is used to illustrate our method.
19.
S. B. Damelin A. B. J. Kuijlaars 《Transactions of the American Mathematical Society》1999,351(11):4561-4584
The support of the equilibrium measure associated with an external field of the form , , with and a positive integer is investigated. It is shown that the support consists of at most two intervals. This resolves a question of Deift, Kriecherbauer and McLaughlin.
20.
Ch. Dorschfeldt N. N. Tarkhanov 《Transactions of the American Mathematical Society》1999,351(2):581-594
Let be an elliptic system with real analytic coefficients on an open set and let be a fundamental solution of Given a locally connected closed set we fix some massive measure on . Here, a non-negative measure is called massive, if the conditions and imply that We prove that, if is a solution of the equation in then for each relatively compact open subset of and every there exist a solution of the equation in and a sequence () in satisfying such that for This complements an earlier result of the second author on representation of solutions outside a compact subset of