=================================================== Vrije Universiteit Amsterdam PhD position in Theoretical Computer Science Project title: Proving equations for cyclic objects =================================================== In the Section of Theoretical Computer Science of the Vrije Universiteit in Amsterdam there is a position for a PhD student for 4 years on the research project Proving Equations For Cyclic Objects Starting date of this PhD position is as soon as possible. The project ----------- This project considers equations between infinite objects, such as streams of 0 and 1. An example equation is morse = 1:0:zip(tail(morse),inv(tail(morse))) defining the famous Thue-Morse sequence 1001011001101001..., satisfying the equation odd(morse) = morse. While proof systems for infinite regular objects are well-known, we study in this project proof systems for more general infinite objects, also non-regular, such as the example stream. We aim to develop and study proof systems of various nature, employing fixed-point rules, coinductive proof rules, or proof procedures based on bisimulation. Relations with coalgebra will be explored as well as with infinitary term rewriting. Aspects of definability of infinite objects will be investigated. Where possible, theory will be developed that is relevant for automated equation provers. For more detailed information see the full project proposal at: http://www.cs.vu.nl/~tcs/ProvCyc.pdf The research will be in the broader framework of the section's main themes: formal methods, term rewriting, process algebra, coalgebra. Qualifications -------------- Candidates must have a masters degree in computer science, mathematics or logic, preferably with knowledge of topics such as automata theory, lambda calculus, type theory, term rewriting or proof theory. Contact and application ----------------------- For further information about this position please contact: Prof.dr. J.W. Klop, jwk@cs.vu.nl, phone: +31 (0)20 5987770 or Dr. R.C. de Vrijer, rdv@cs.vu.nl, phone: +31 (0)20 5987770 You are invited to send an application by email to rdv@cs.vu.nl, no later than May 1, 2005. Your application should consist of a cover letter, a curriculum vitae (including detailed information regarding your academic degree and possible publications) and the names and addresses of two references.