Radon-Nikodym theorem in quasi *-algebras

In this paper some properties of continuous representable linear functionals on a quasi $*$-algebra are investigated. Moreover we give properties of operators acting on a Hilbert algebra, whose role will reveal to be crucial for proving a Radon-Nikodym type theorem for positive linear functionals.

Rademacher Theorem for Fréchet spaces

Abstract Let X be a separable Frechet space. In this paper we define a class A of null sets in X that is properly contained in the class of Aronszajn null sets, and we prove that a Lipschitz map from an open subset of X into a Gelfand-Frechet space is Gateaux differentiable outside a set belonging to A. This is an extension to Frechet spaces of a result (see [PZ]) due to D. Preiss and L. Zajicek.

Differentiability of Lipschitz maps

A decomposition theorem for σ-P-directionally porous sets in Fréchet spaces

In this paper we study suitable notions of porosity and directional porosity in Fréchet spaces. Moreover we give a decomposition theorem for $\sigma$-$\mathcal{P}$-directionally porous sets.