Lawrence Paulson – Proof Assistants: From symbolic logic to real mathematics?
Jean-Christophe Thalabard viendra nous présenter ses travaux le 18 mai 2017.
L'intitulé de son exposé : "Proof Assistants: From symbolic logic to real mathematics?".
- Date : 18/05/2017
- Lieu : Inria, Sophia Antipolis, Bâtiment Kahn
- Intervenants : Lawrence Paulson, Professeur, Université de Cambridge
- Organisateurs : Comité du Colloquium
Résumé (la présentation sera en anglais)
Mathematicians have always been prone to error. As proofs get longer and more complicated, the question of correctness looms ever larger. Andrew Wiles’ proof of Fermat’s last theorem contained a flaw that was only fixed a year later. Meanwhile, proof assistants — formal tools originally developed in order to verify hardware and software — are growing in sophistication and are being applied more and more to mathematics itself. When will proof assistants finally become useful to working mathematicians?
Mathematicians have used computers in the past, for example in the 1976 proof of the four colour theorem, and through computer algebra systems such as Mathematica. However, many mathematicians regard such proofs as suspect. Proof assistants (e.g. Coq, HOL and Isabelle/HOL) are implementations of symbolic logic and were originally primitive, covering only tiny fragments of mathematical knowledge. But over the decades, they have grown in capability, and in 2005, Gonthier used Coq to create a completely formal proof of the four colour theorem. More recently, substantial bodies of mathematics have been formalised. But there are few signs of mathematicians adopting this technology in their research.
Today’s proof assistants offer expressive formalisms and impressive automation, with growing libraries of mathematical knowledge. More however must be done to make them useful to mathematicians. Formal proofs need to be legible with a clear connection to the underlying mathematical ideas. Natural language must play a stronger role, and our millions of lines of existing proofs surely contain hints to aid in the construction of new proofs.