Impossible futures and determinism

Liveness, Fairness and Impossible Futures

Impossible futures equivalence is the semantic equivalence on labelled transition systems that identifies systems iff they have the same “AGEF” properties: temporal logic properties saying that reaching a desired outcome is not doomed to fail. We show that this equivalence, with an added root condition, is the coarsest congruence containing weak bisimilarity with explicit divergence that respec...

On the Axiomatizability of Impossible Futures

A general method is established to derive a ground-complete axiomatization for a weak semantics from such an axiomatization for its concrete counterpart, in the context of the process algebra BCCS. This transformation moreover preserves ω-completeness. It is applicable to semantics at least as coarse as impossible futures semantics. As an application, groundand ω-complete axiomatizations are de...

On Finite Bases for Weak Semantics: Failures Versus Impossible Futures

We provide a finite basis for the (in)equational theory of the process algebra BCCS modulo the weak failures preorder and equivalence. We also give positive and negative results regarding the axiomatizability of BCCS modulo weak impossible futures semantics.

Laplace , Turing and the " imitation game " impossible geometry : randomness , determinism and programs in Turing ' s test

: From the physico-mathematical view point, the imitation game between man and machine, proposed by Turing in 1950, is a game between a discrete and a continuous system. Turing stresses several times the laplacian nature of his discrete-state machine, yet he tries to show the undetectability of a functional imitation, by his machine, of a system (the brain) that, in his words, is not a discrete...

Climate and Weather Discourse in Anthropology: From Determinism to Uncertain Futures