## Special talks

#### Future talks

Exposés hors-séries

jeudi 05 juillet 2018, 14h00, Salle 3052

**Laurent Viennot** (Inria Paris et IRIF) *Introduction to the blockchain*

The collaborative construction of a blockchain is the core of Bitcoin protocol for allowing various participants to agree on a list of valid transactions. The talk will be very informal, the intent is to give a very basic introduction on how Bitcoin works and highlight some of the scientific challenges behind it.

#### Past talks

Exposés hors-séries

mardi 20 février 2018, 14h00, 3052

**Daniela Petrisan** (IRIF) *Up-To Techniques for Behavioural Metrics via Fibrations*

Up-to techniques are a well-known method for accelerating proofs of

behavioural equivalences between systems. In this talk, I introduce up-to techniques for behavioural metrics in a coalgebraic setting and provide general results that show under which conditions such up-to techniques are sound.

For a system modelled as a coalgebra for a certain functor, the behavioural distance can be seen as a coinductive predicate using a suitable lifting of the functor. I will focus on the so called Wasserstein lifting of a functor for which we provide a new characterization in a fibrational setting. This is useful for automatically proving the soundness of up-to techniques via a generic framework developed in a previous CSL-LICS'14 paper.

I will use fibrations of predicates and relations valued in a quantale, for which pseudo-metric spaces are an example. To illustrate our framework I provide an example on distances between regular languages.

Exposés hors-séries

jeudi 01 février 2018, 14h00, 3052

**Vincent Danos** (ENS) *Contractivity of Markov chains (metric couplings)*

The module is a continuation of the lecture series by Prakash Panangaden on Labelled Markov Processes, but can be independently followed.

Exposés hors-séries

mardi 30 janvier 2018, 14h00, 3052

**Vincent Danos** (ENS) *Bayesian inversion and approximation*

The module is a continuation of the lecture series by Prakash Panangaden on Labelled Markov Processes, but can be independently followed.

Exposés hors-séries

jeudi 25 janvier 2018, 14h00, 3052

**Prakash Panangaden** (McGill University) *Quantitative equational logic and free Kantorovich algebras*

Prakash will open his stay with a series of 4 introductory lectures on probabilistic systems: “Introduction to Labelled Markov Processes”

Exposés hors-séries

mardi 23 janvier 2018, 14h00, 3052

**Prakash Panangaden** (McGill University) *Metrics for LMPs*

Prakash will open his stay with a series of 4 introductory lectures on probabilistic systems: “Introduction to Labelled Markov Processes”

Exposés hors-séries

jeudi 18 janvier 2018, 14h00, 3052

**Prakash Panangaden** (McGill University) *A dual point of view: LMPs as function transformers*

Prakash will open his stay with a series of 4 introductory lectures on probabilistic systems: “Introduction to Labelled Markov Processes”

Exposés hors-séries

mardi 16 janvier 2018, 14h00, 3052

**Prakash Panangaden** (McGill University) *Introduction to LMPs: bisimulation, simulation, logical characterization*