Etienne Duchesne (Paris, France), MELL in a free compact closure


  • Feb. 8, 2012, 16:00 - 16:45


The categorical presentation of the standard model of the geometry of interaction --namely the free compact closure of sets and partial injections Int(PInj)-- fails to be a denotational semantics of MELL. The work of Melli├Ęs, Tabareau & Tasson on the formula for a free exponential modality gives us insights into the reasons of this failure: absence of free pointed objects, absence of equalizers of some groups of permutations... We will present generic constructions which successively add the algebraic structure needed to compute this formula, and show that the usual model of GoI wrapped in these successive layers defines a denotational semantics of MELL.