We study the commutativity of two operations: quotienting and completing. Completing refers to the countable chain completion, known to exist for every partial order, and quotienting is with respect to a semigroup congruence. The two operations are shown to commute in a suitable framework. We apply the results for studying the semigroup structure and topological semigroup structure on the completion.

We introduce the model of Markov nets, a probabilistic extension of safe Petri nets under the true-concurrency semantics. This means that traces, not firing sequences, are given a probability. This model builds upon our previous work on probabilistic event structures. We use the notion of branching cell for event structures and show that the latter provides the adequate notion of local state, for nets. We prove a Law of Large Numbers (LLN) for Markov nets, which constitutes the main contribution of the paper. This LLN allows characterizing in a quantitative way the asymptotic behavior of Markov nets.

This paper introduces projective systems for topological and probabilistic event structures. The projective formalism is used for studying the domain of configurations of a prime event structure and its space of maximal elements. This is done from both a topological and a probabilistic viewpoint. We give probability measure extension theorems in this framework.

We revisit extension results from continuous valuations to Radon measures for bifinite domains. In the framework of bifinite domains, the Prokhorov theorem (existence of projective limits of Radon measures) appears as a natural tool, and helps building a bridge between Measure theory and Domain theory. The study we present also fills a gap in the literature concerning the coincidence between projective and Lawson topology for bifinite domains. Motivated by probabilistic considerations, we study the extension of measures in order to define Borel measures on the space of maximal elements of a bifinite domain.

We introduce a new class of morphisms for event structures. The category obtained is cartesian closed, and a natural notion of quotient event structure is defined within it. We study in particular the topological space of maximal configurations of quotient event structures. We introduce the compression of event structures as an example of quotient: the compression of an event structure E is a minimal event structure with the same space of maximal configurations as E.

This paper is devoted to probabilistic models for concurrent systems under their true-concurrency seman- tics. Here we address probabilistic event structures. We consider a new class of event structures, called locally finite, that extend confusion-free event structure. In locally finite event structures, maximal configurations can be tiled with branching cells: branching cells are minimal and finite sub-structures capturing the choices performed while scanning a maximal configuration. The probabilistic event structures that we introduce have the property that concurrent processes are independent in the probabilistic sense.