Quantifier Elimination and its Applications Session organizers: Richard Liska Michael Jahn Abstract: An algorithm for quantifier elimination (QE) over real closed fields (in particular, the reals R) has been known for quite a long time, but its first and only fully practical implementation, using the partial cylindrical algebraic decomposition algorithm developed by Collins and Hong, appeared only several years ago. It is known that this general QE procedure will terminate in a finite number of steps for any quantifier elimination problem. However, its time complexity is double exponential, so the applicability of this procedure is limited to rather small sized problems. Recently, several specialized procedures solving quantifier elimination problems of a particular type have appeared. These specialized algorithms allow treatment of more complicated problems, in particular, the inclusion of more free, unquantified variables. The QE method has been applied to inverse kinematics, optimization, stability, geometric theorem proving and other problems. However, its potential for applications has not yet been fully revealed due to the ongoing development of specialized algorithms for restricted types of QE problems (to address the limitation of high time complexity for the general QE method). The session will concentrate on special QE methods and applications of QE. The aim of this session is to bring together two groups of people, the first one working on QE, and the second one interested in QE applications in different branches of science. Tentative list of speakers to be invited: G. Collins H. Hong J. Johnson R. Liska S. McCallum S. Steinberg V. Weispfenning L. Gonzales-Vega T. Recio J. Renegar M.F. Roy