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.

About the speaker

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).

Event Topic

Distinguished Lecture Series