Poisson Lie Groups and Non-Linear Convexity Theorems

In this paper we describe how one can derive nonlinear convexity theorems which are similar to Kostant's nonlinear convexity theorem for the Iwasawa decomposition from Hamiltonian actions on Poisson Lie groups. Our results generalize those of LU and Ratiu ([24]) and aim at a unified symplectic framework for the convexity theorem in [32] and the linear convexity theorems for coadjoint orbits of convex type in [15].     

Convexity and unitary representations of nilpotent Lie groups

Summary The moment map of symplectic geometry is extended to associate to any unitary representation of a nilpotent Lie group aG-invariant subset of the dual of the Lie algebra. We prove that this subset is the closed conex hull of the Kirillov orbit of the representation.Supported by NSERC research grant no. A7918     

Holomorphy in convergence spaces

We introduce a new approach to infinite dimensional holomorphy. Cast in the setting of closed-embedded linear convergence spaces and based on a categorical definition of derivative, our theory applies beyond the traditional open domains. It reaches certain domains with empty interior (that arise naturally in Fréchet spaces) and gives a fully fledged differential calculus. On open domains our approach provides a new characterization of holomorphic maps. Thus earlier theories become expanded as well as strengthened.NSERC aided     

Approximation on Subsets and Holomorphy in Neighborhood

Let M be an arbitrary subset of the complex plane C, and let a function f; be defined on M. The connection between the holomorphy of f; and the degree of the best polynomial approximation of f; on compact subsets of M having a unique limit point is described.     

Morse Theory And Invariant Concepts of Convexity

In optimization, the literature on invariant definitions of convexity has largely centered on the notion of invexity. However, the connection with Morse theory and related geometric trends has not been recognized and results do not appear to be as impressive as those in topology. Our purpose is to improve the situation in optimization, and to clarify the relationship between these two trends. The main result is that the problem can be reduced to the case of functions of one variable.     

参数曲面保凸的一个定理

本文讨论了参数曲面的凸性，给出了参数曲面为凸的充要条件．并给出了具体的应用实例．     

F─广义凸多目标规划的对偶理论

本文讨论Ｆ—广义凸多目标规划的对偶理论，证明了弱对偶、直接对偶和逆对偶定理．主要结果参考文献［１］的推广和发展。     

Convexity and the Exterior Inverse Problem of Potential Theory

Let and be bounded solid domains such that their associated volume potentials agree outside . Under the assumption that one of the domains is convex, it is deduced that .

     

On a Bornological Structure in Infinite-Dimensional Holomorphy

The bornology (b) of bounded subsets with respect to continuous convergence is used on spaces of holomorphic functions. It is shown that Hom_coH_b(U) ? U for a circled convex open subset U of a complete nuclear space. Exponential laws for spaces of holomorphic functions with bornological structures are proved and the connection with Colombeau's Silva holomorphic functions is established.     

Quantum Graphs with Small Edges: Holomorphy of Resolvents

Doklady Mathematics - We consider a general scalar self-adjoint elliptic second order operator with general boundary conditions on an arbitrary metric graph containing a subgraph with edges of...     

Domains of Holomorphy with Edges and Lower Dimensional Boundary Singularities

It is shown that a domain in C ^N with piecewise smooth boundary (and also of some more general shape) is a domain of holomorphy, provided the Levi form at every regular point is positively semidefinite and the tangent cone is convex at every point outside a boundary subset of zero Hausdorff (2N-2)-dimensional measure.