Fixed-parameter tractable reductions to SAT
Ronald de Haan,
TU Wien –
Modern propositional satisfiability (SAT) solvers perform extremely well in many practical settings and can be used as an efficient back-end for solving NP-complete problems. However, many fundamental problems in Knowledge Representation and Reasoning are located at the second level of the Polynomial Hierarchy (PH) or even higher, and hence for these problems polynomial-time transformations to SAT are not possible, unless the PH collapses. Recent research shows that in certain cases one can break through these complexity barriers by fixed-parameter tractable (fpt) reductions which exploit structural aspects of problem instances in terms of problem parameters.
We develop a general theoretical framework that supports the classification of parameterized problems on whether they admit such an fpt-reduction to SAT or not. We base this framework on its application to concrete reasoning problems from various domains. We develop several parameterized complexity classes to provide evidence that in certain cases such fpt-reductions to SAT are not possible. Moreover, we relate these new classes to existing parameterized complexity classes. Additionally, for problems for which there exists a Turing fpt-reduction to SAT, we develop techniques to provide lower bounds on the number of calls to a SAT solver needed to solve these problems.
Date: 2014-Apr-02 Time: 14:00:00 Room: 336
For more information:
Workshop “Metabolism and mathematical models: Two for a tango” – 2nd Edition
Title: Workshop Metabolism and mathematical models: Two for a tango – 2nd Edition
Dates: October 25-26, 2022
Location: This workshop will be held in a virtual way
The topic of this workshop is metabolism in general, with a special focus, although not exclusive, on parasitology. Besides an exploration of the biological, biochemical and biomedical aspects, the workshop will also aim at presenting some of the mathematical modelling, algorithmic theory and software development that have become crucial to explore such aspects.
This workshop is being organised in the context of two projects, both with the Inria European Team Erable. One of the projects involves a partnership with the University of São Paulo (USP), in São Paulo, Brazil, more specifically the Institute of Mathematics and Statistics (IME) and the Institute of Biomedical Sciences – Inria Associated Team Capoeira – and the other involves the Inesc-ID/IST in Portugal, ETH in Zürich and EMBL in Heidelberg – H2020 Twinning Project Olissipo.
The workshop is open to all members of these two projects but also, importantly, to the community in general.
The program and more details are available here.