Michael Benedikt, Oxford University.
Professor at Department of Computer Science, Oxford University, UK.
The Past and Future of Embedded Finite Model TheoryEmbedded finite model theory refers to a formalism for describing finite structures over an uninterpreted signature, which sit within an infinite interpreted structures. Some theory was developed in the 1990’s and early 2000’s, with a focus on the real field. But the theory applies to arbitrary theories, and is relevant to recent development on graph querying and analysis of data-driven programs involving arithmetic.
In this invited paper we review the framework and some of the basic results on it. We also discuss some open questions, along with some work in progress, joint with Ehud Hrushovski.
Laura Ciobanu, Heriot-Watt University.
Co-director of Maxwell Institute, Heriot-Watt University, UK.
Post's Correspondence Problem: from computer science to algebraIn this short survey we describe recent advances on the Post Correspondence Problem in group theory that were inspired by results in computer science. These algebraic advances can, in return, provide a source of interesting problems in more applied, computational settings.
Post’s Correspondence Problem (PCP) is a classical decision problem in theoretical computer science that asks whether for a pair of free monoid morphisms g,h : Σ*→ Δ* there is any x ∈ Σ* such that g(x) = h(x). One can similarly phrase a PCP for general groups, rather than free monoids, by asking whether pairs g,h of group homomorphisms agree on any inputs. This leads to interesting and unexpected (un)decidability results for PCP in groups.
Wojciech CzerwiĆski, University of Warsaw.
Assistant professor at the Institute of Informatics, Faculty of Mathematics, Informatics and Mechanics of the University of Warsaw, Poland.
Recent Advances on the Reachability Problem for VASSes by ExamplesI will briefly describe recent advances on understanding the complexity of the reachability problem for vector addition systems (or equivalently for vector addition systems with states - VASSes). I plan to present a few involved VASS examples in small dimensions, which illustrate various aspects of hardness of VASSes and various techniques of proving lower complexity bounds. If time allows I will also briefly discuss VASSes with a stack.
Rupak Majumdar, MPI-SWS.
Scientific Director, MPI-SWS, Germany.
Decidability Results for Context-Bounded Analysis of SystemAutomated analysis of multithreaded shared memory programs is a core problem in verification. While the general verification problem for these systems is undecidable, already when there are only two recursive threads, there has been a lot of work to find appropriate underapproximations. Context-bounding is one such underapproximation technique. In context bounded analysis, we set an a priori bound K and restrict attention to only those runs of the system in which each thread is interrupted at most K times. It turns out that many verification problems become decidable under the restriction of context bounding. In this talk, I will provide a survey of recent results in this area. Specifically, we shall consider context-bounded safety and liveness verification for systems in which threads can spawn new threads, as well as practically-motivated restrictions of the problem such as thread pooling. (Joint work with Pascal Baumann, Moses Ganardi, Ramanathan Thinniyam, and Georg Zetzsche.)
Sharon Shoham Buchbinder, Tel Aviv University.
Associate professor in the School of Computer Science at Tel Aviv University, Israel.
SAT-Based Invariant Inference and Its Relation to Concept LearningThis paper surveys results that establish formal connections and distinctions between SAT-based invariant inference and exact concept learning with queries, showing that learning techniques and algorithms can clarify foundational questions, illuminate existing algorithms, and suggest new directions for efficient invariant inference.