Thu 21 Jan 2016 17:20 - 17:45 at Grand Bay South - Track 2: Sessions and processes Chair(s): Matteo Maffei

Environmental bisimulations in probabilistic higher-order languages are studied. In contrast with applicative bisimulations, environmental bisimulations are known to be more robust and do not require sophisticated techniques such as Howe’s in the proofs of congruence.

As representative calculi, call-by-name and call-by-value $\lambda$-calculus, and a (call-by-value) $\lambda$-calculus extended with references (i.e., a store) are considered. In each case full abstraction results are derived for probabilistic environmental similarity and bisimilarity with respect to contextual preorder and contextual equivalence, respectively. Some possible enhancements of the (bi)simulations, as `up-to techniques’, are also presented.

Probabilities force a number of modifications to the definition of environmental bisimulations in non-probabilistic languages. Some of these modifications are specific to probabilities, others may be seen as general refinements of environmental bisimulations, applicable also to non-probabilistic languages. Several examples are presented, to illustrate the modifications and the differences.

#### Thu 21 Jan Times are displayed in time zone: Guadalajara, Mexico City, Monterrey change

 16:30 - 17:45 Track 2: Sessions and processesResearch Papers at Grand Bay South Chair(s): Matteo MaffeiSaarland University 16:3025mTalk Effects as sessions, sessions as effectsResearch PapersDominic OrchardImperial College London, Nobuko YoshidaImperial College London, UK Pre-print Media Attached 16:5525mTalk Monitors and Blame Assignment for Higher-Order Session TypesResearch PapersLimin JiaCarnegie Mellon University, Hannah GommerstadtCarnegie Mellon University, Frank PfenningCarnegie Mellon University Media Attached File Attached 17:2025mTalk Environmental Bisimulations for Probabilistic Higher-Order LanguagesResearch PapersDavide SangiorgiUniversity of Bologna, Valeria VignudelliUniversity of Bologna/INRIA Media Attached