English

Some Geometric Aspects Related to Lim's Condition

Functional Analysis 2026-02-04 v3

Abstract

In their seminal work, Lau and Mah (1986) study ww^*-normal structure in the space of operators L(H)\mathcal{L}(H), on a Hilbert space HH, using a geometric property of the dual unit ball called Lim's condition. In this paper, we study a weaker form of Lim's condition, which we call property (\ddagger), for CC^\ast-algebras, uniform algebras, and L1L^1-predual spaces. In the case of a CC^\ast-algebra, we prove that property ()(\ddagger) is equivalent to Lim's condition and consequently, we obtain a geometric characterization of CC^*-algebras which are c0c_0-direct sum of finite-dimensional operator spaces. For a uniform algebra, we extend a result of Lau and Mah to show that property ()(\ddagger) implies that the space is finite-dimensional. In the case of an L1L^1-predual space, we show that this condition implies kk-smoothness of the norm in the sense considered in Lin and Rao (2007).

Keywords

Cite

@article{arxiv.2504.09464,
  title  = {Some Geometric Aspects Related to Lim's Condition},
  author = {Deepak Gothwal and T. S. S. R. K. Rao},
  journal= {arXiv preprint arXiv:2504.09464},
  year   = {2026}
}

Comments

Previous version was named as Lim's condition and differentiability. The new file consists of the discussion from a different viewpoint and some new results like the equivalence of property $(\ddagger)$ and Lim's condition in $C^*$-algebras have been obtained

R2 v1 2026-06-28T22:56:26.689Z