 What are the general structural properties of a space of partial data? The mathematical theory of computation elaborated by Dana Scott (1970) is an answer to this question, that takes partially ordered sets generically called domains as basic structures. The partial order of a domain describes a qualitative notion of “information” carried by the elements. In such a framework it is natural to reify divergence by introducing a new element \(\bot\) representing absence of information. When \(x \sqsubseteq y\) in this partial order, 