IRIF Distinguished Talks Series Friday October 28, 2016, 10:30AM, Salle 3052, Bâtiment Sophie Germain (SEE NOTE IN THE ABSTRACT) Yuri Gurevich (Microsoft Research) IRIF expository talks series : Logic in Computer Science and Computer Engineering In software industry, engineers do formal logic day in and day out, even though they may not realize that. As a rule, they have not studied logic. Instead, they spent a lot of time studying calculus which they use rarely, if ever. I'll try to illustrate why logic is so relevant and why it is hard for software engineers to pick it up. IMPORTANT NOTE: For administrative reasons, those from outside of IRIF who wish to attend the seminar in “Salle 3052” should email by Wednesday 26/10 their name to Irène Guessarian at ig@liafa.univ-paris-diderot.fr . IRIF Distinguished Talks Series Friday September 16, 2016, 10:30AM, Amphi Turing (Bâtiment Sophie Germain) Roberto Di Cosmo (IRIF) IRIF expository talks series: Preserving Software: challenges and opportunities for the reproductibility of Science (click here for the slides) A vast amount of modern scientific and technological knowledge relies on the software that we have been collectively writing: deep knowledge from fields like mathematics, physics, chemistry, biology, medicine, finance and social sciences is now inextricably embodied into complex software systems, which model it at a level of detail that goes way beyond that of the usual scientific publications. Preserving this software is of paramount importance to preserve our knowledge. It is is a necessary prerequisite to allow the replication of experiments, which is the foundation of the scientific method, as well as to ensure our ability to modify and correct the software components that are constantly being incorporated into critical systems that need to stay in production for decades. In this talk, we will review the challenges and opportunities we are facing, and discuss the role of Open Source as a key enabler. The slides of the talk can be found here. IRIF Distinguished Talks Series Thursday January 28, 2016, 10:30AM, Amphi Turing Nachum Dershowitz (Tel Aviv University) Ada and Computation Ada Lovelace (born 200 years ago) wrote presciently about digital numerical calculations. She expressed its features poetically: “We may say most aptly that [Babbage's] Analytical Engine weaves algebraical patterns just as the Jacquard loom weaves flowers and leaves.” Ada explained the generality of digital computation, saying that “the engine can arrange and combine its numerical quantities exactly as if they were letters or any other general symbols.” We will discuss some of the expected and unexpected consequences of alternate representations of computational data. On the other hand, Ada wrote that “the engine [is] the material expression of any indefinite function of any degree of generality and complexity.” This we now know was overstating her case. We will discuss the formalization of the notion of effective computation and its consequences vis-a-vis computability and complexity of computation. Nachum Dershowitz has been a professor of computer science at Tel Aviv University since 1998. Prior to that, he was on the faculty of the University of Illinois at Urbana-Champaign. He coauthored the book, Calendrical Calculations (Cambridge University Press, 1997), with Edward Reingold, which won Choice's Outstanding Academic Title Award (2002) and is about to go into its fourth edition. He is also the author of The Evolution of Programs (Birkhäuser, 1983), coauthor of Calendrical Tabulations (Cambridge University Press, 2002), and editor of a dozen other volumes. His research interests include foundations of computing, computational logic, computational humanities, and combinatorial enumeration. He has received the Herbrand Award (2011), LICS Test-of-Time Award (2006), RTA Test-of-Time Award (2014) and Skolem Award (2015) and has been elected to Academia Europaea (2013).