Decomposition Numbers and Canonical Bases

We obtain some simple relations between decomposition numbers of quantized Schur algebras at an nth root of unity (over a field of characteristic 0). These relations imply that every decomposition number for such an algebra occurs as a decomposition number for some Hecke algebra of type A. We prove similar relations between coefficients of the canonical basis of the q-deformed Fock space representation of . It follows that these coefficients can all be expressed in terms of those of the global crystal basis of the irreducible subrepresentation generated by the vacuum vector. As a consequence, using the works of Ariki and Varagnolo and Vasserot, it is possible to give a new proof of Lusztig"s character formula for the simple U _v (sl _r )-modules at roots of unity, which does not involve representations of of negative level.     

Chaotic Dynamics of Monotone Twist Maps

For a monotone twist map, under certain non-degenerate condition, we showed the existence of infinitely many homoclinic and heteroclinic orbits between two periodic neighboring minimal orbits with the same rotation number, which indicates chaotic dynamics. Our results also apply to geodesics of smooth Riemannian metrics on the two-dimension torus.     

扭转映射的Aubry－Mather理论及其应用

本文介绍Ａｕｂｒｙ－Ｍａｔｈｅｒ理论近年来的发展情况，文章讨论了该理论与ＫＡＭ理论、保面积映射不动点理论的联系，并简单地介绍了它的一些推广。作为该理论的应用，对平面Ｈａｍｉｌ－ｔｏｎ系统Ｍａｔｈｅｒ集的存在性给出了一些结果．     

扭转映射的一个不动点定理

本文利用集连通理论，给出了非保面积的扭转映射至少有两个不动点的一个新定理．     

Computing Canonical Polygonal Schemata with Generalized Maps

This paper shows that a well-known algorithm proposed to compute the canonical polygonal schema of a surface can be transferred onto a 2-dimensional generalized map. We show that transformation rules on polygonal schemata can be achieved in O(1) with generalized maps, which can help optimizing existing algorithms.     

Normal Bases and Their Dual-Bases over Finite Fields

In this paper, we prove the following results： 1） A normal basis N over a finite field is equivalent to its dual basis if and only if the multiplication table of N is symmetric; 2） The normal basis N is self-dual if and only if its multiplication table is symmetric and Tr（α^2） = 1, where α generates N; 3） An optimal normal basis N is self-dual if and only if N is a type-Ⅰ optimal normal basis with q = n = 2 or N is a type-Ⅱ optimal normal basis.     

Dual Bases for a New Family of Generalized Ball Bases

This paper presents the dual bases for a new family of generalized Ball curves with a position parameter K, which includes the Bezier curve, generalized Said-Ball curve and some intermediate curves. Using the dual bases, the relative Marsden identity, conversion formulas of bases and control points of various curves are obtained.     

Canonical Models for the Forward and Backward Iteration of Holomorphic Maps

We prove the existence and the essential uniqueness of canonical models for the forward (resp., backward) iteration of a holomorphic self-map f of a cocompact Kobayashi hyperbolic complex manifold, such as the ball \(\mathbb {B}^q\) or the polydisc \(\Delta ^q\). This is done by performing a time-dependent conjugacy of the autonomous dynamical system defined by f, obtaining in this way a non-autonomous dynamical system admitting a relatively compact forward (resp., backward) orbit, and then proving the existence of a natural complex structure on a suitable quotient of the direct limit (resp., subset of the inverse limit). As a corollary we prove the existence of a holomorphic solution with values in the upper half-plane of the Valiron equation for a hyperbolic holomorphic self-map of the unit ball.     

Bitableaux and Zero Sets of Dual Canonical Basis Elements

We state new results concerning the zero sets of polynomials belonging to the dual canonical basis of mathbbC[x₁, 1, . . . , x_n, n]{mathbb{C}[x_1, 1, . . . , x_n, n]} . As an application, we show that this basis is related by a unitriangular transition matrix to the simpler bitableau basis popularized by Désarménien-Kung-Rota. It follows that spaces spanned by certain subsets of the dual canonical basis can be characterized in terms of products of matrix minors, or in terms of their common zero sets.     

The Canonical Dual Frame of a Wavelet Frame

In this paper we show that there exist wavelet frames that have nice dual wavelet frames, but for which the canonical dual frame does not consist of wavelets, i.e., cannot be generated by the translates and dilates of a single function.     

Crystal Bases for Quantum Generalized Kac-Moody Algebras

In this paper, we develop the crystal basis theory for quantumgeneralized Kac–Moody algebras. For a quantum generalizedKac–Moody algebra U_q(g), we first introduce the categoryO_int of U_q(g)-modules and prove its semisimplicity. Next, wedefine the notion of crystal bases for U_q(g)-modules in thecategory O_int and for the subalgebra . We then prove the tensor product rule and the existence theoremfor crystal bases. Finally, we construct the global bases forU_q(g)-modules in the category O_int and for the subalgebra . 2000 Mathematics Subject Classification17B37, 17B67.     

Weyl Laws for Partially Open Quantum Maps

We study a toy model for “partially open” wave-mechanical system, like for instance a dielectric micro-cavity, in the semiclassical limit where ray dynamics is applicable. Our model is a quantized map on the 2-dimensional torus, with an additional damping at each time step, resulting in a subunitary propagator, or “damped quantum map”. We obtain analogues of Weyl’s laws for such maps in the semiclassical limit, and draw some more precise estimates when the classical dynamics is chaotic. Submitted: October 16, 2008. Accepted: April 3, 2009.     

Dual Wavelet Frames and Riesz Bases in Sobolev Spaces

This paper generalizes the mixed extension principle in L ₂(ℝ ^d ) of (Ron and Shen in J. Fourier Anal. Appl. 3:617–637, 1997) to a pair of dual Sobolev spaces H ^s (ℝ ^d ) and H ^−s (ℝ ^d ). In terms of masks for φ,ψ ¹,…,ψ ^L ∈H ^s (ℝ ^d ) and , simple sufficient conditions are given to ensure that (X ^s (φ;ψ ¹,…,ψ ^L ), forms a pair of dual wavelet frames in (H ^s (ℝ ^d ),H ^−s (ℝ ^d )), where

由箭图构造的对偶Hopf代数和量子群

在文献[3]和[6]中,Hopf箭图的路代数上的Hopf代数结构和覆盖箭图的路余代数上的Hopf代数结构分别被给出.该文通过一个箭图是Hopf箭图当且仅当它是箭图覆盖这一结论,来讨论同一箭图上给出的这两种Hopf代数结构之间的对偶关系(见定理3和定理4).作为应用,作者先得到关于定向圈的路代数的商上的Hopf代数结构的一些性质,然后证明了Sweedler的4维-Hopf代数小仅是拟三角的而且是余拟三角的.最后,作者刻画了Schurian覆盖箭图的路代数上的Hopf代数的分次自同构群.     

Quantum Unique Ergodicity for Maps on the Torus

When a map is classically uniquely ergodic, it is expected that its quantization will posses quantum unique ergodicity. In this paper we give examples of Quantum Unique Ergodicity for the perturbed Kronecker map, and an upper bound for the rate of convergence. submitted 3/02/05, accepted 20/10/05     

A Parameterization of the Canonical Bases of Affine Modified Quantized Enveloping Algebras

For a symmetrizable Kac-Moody Lie algebra g, Lusztig introduced the corresponding modified quantized enveloping algebra˙U and its canonical basis˙B given by Lusztig in 1992. In this paper, in the case that g is a symmetric Kac-Moody Lie algebra of finite or affine type, the authors define a set M which depends only on the root category R and prove that there is a bijection between M and ˙B, where R is the T~2-orbit category of the bounded derived category of the corresponding Dynkin or tame quiver. The method in this paper is based on a result of Lin, Xiao and Zhang in 2011, which gives a PBW-type basis of U~+.