English

On the global shape of convex functions on locally convex spaces

Functional Analysis 2020-01-22 v1

Abstract

In the recent paper \cite{Aza:19} D Azagra studies the global shape of continuous convex functions defined on a Banach space XX. More precisely, when XX is separable, it is shown that for every continuous convex function f:XRf:X\rightarrow\mathbb{R} there exist a unique closed linear subspace YY of XX, a continuous function h:X/YRh:X/Y\rightarrow\mathbb{R} with the property that limth(u+tv)=\lim_{t\rightarrow\infty}h(u+tv)=\infty for all u,vX/Yu,v\in X/Y, v0v\neq0, and xXx^{\ast}\in X^{\ast} such that f=hπ+xf=h\circ\pi+x^{\ast}, where π:XX/Y\pi :X\rightarrow X/Y is the natural projection. Our aim is to characterize those proper lower semi\-continuous convex functions defined on a locally convex space which have the above representation. In particular, we show that the continuity of the function ff and the completeness of XX can be removed from the hypothesis of Azagra's theorem.

Keywords

Cite

@article{arxiv.2001.07007,
  title  = {On the global shape of convex functions on locally convex spaces},
  author = {Constantin Zalinescu},
  journal= {arXiv preprint arXiv:2001.07007},
  year   = {2020}
}

Comments

The paper has 12 pages