Venue: San Francisco, California

Conference dates:
CONCUR: 23-26 August 2005
GETCO: 21 August 2005

Recently, ideas and notions from mainstream "geometric" topology and algebraic topology have entered the scene in Concurrency Theory and Distributed Systems Theory (some of them based on older ideas). They have been applied in particular to problems dealing with coordination of multi-processor and distributed systems (see the historical note ). Among those are techniques borrowed from algebraic and geometric topology: Simplicial techniques have led to new theoretical bounds for coordination problems. Higher dimensional automata have been modeled as cubical complexes with a partial order reflecting the time flows, and their homotopy properties allow to reason about a system's global behaviour.

The GETCO workshops aim at bringing together researchers from both the mathematical (geometry, topology, algebraic topology etc.) and computer scientific side (concurrency theorists, semanticians, algorithmicians, researchers in distributed systems etc.) with an active interest in these or related developments.

Topics include (but are not limited to):

• Algorithmics for Concurrent or Distributed Systems
• Fault-tolerant Protocols for Distributed Systems
• Semantics
• Concurrency Theory
• Model-checking
• Abstract Interpretation
• Geometric/Topological models
• Applications of algebraic topology
• Category theory

• The first workshop on the subject "Geometric and Topological Methods in Concurrency Theory" was held at Aalborg University, Denmark, in June 1999. Volume 10, Issue 4 of Mathematical Structures in Computer Science contains what are commonly considered to be the proceedings of this workshop.
• GETCO 2000 was organised as a workshop affiliated with the CONCUR 2000 conference at Penn State University. The preproceedings are available through the BRICS Notes Series, and the proceedings were published as Volume 39, Issue 2 of the Electronic Notes in Theoretical Computer Science.
• GETCO 2001 was organised as a workshop affiliated with CONCUR 2001 at Aalborg University. The preproceedings are available through the BRICS Notes Series, and the proceedings were published as Volume 52, Issue 2 of the Electronic Notes in Theoretical Computer Science.
• The GETCO 2002 workshop was associated with the DISC 2002 conference at ENSEEIHT Toulouse. The preproceedings are available through the BRICS Notes Series, and the proceedings have been published as Volume 81 of ENTCS.
• GETCO 2003 was an affiliated workshop of the CONCUR 2003 conference in Marseille. Its preproceedings are available through the BRICS Notes Series, and the proceedings have been published as Volume 90, Issue 5 of ENTCS.
• GETCO 2004 was affiliated with DISC 2004 in Amsterdam. The preproceedings are again available through the BRICS Notes Series, and the proceedings will be published with ENTCS.

Electronic submission is strongly encouraged. The paper or abstract should be sent by e-mail in the form of a postscript or PDF file to both the addresses uli@math.aau.dk and Haucourt@cea.fr. The accompanying page should be sent in a separate email message. If surface mail has to be used, then 3 copies of the paper/abstract should be sent to: Emmanuel Haucourt, DTSI/SLA, bat. 528, CEA Saclay, 91191 Gif-sur-Yvette, France.

The deadline for submissions is 1 June 2005.

We expect that as in the years before, the preliminary proceedings of the workshop will published in the BRICS Notes series, and the proceedings with Electronic Notes in Theoretical Computer Science. The details of this are still under negotiation.

• Patrick Cousot, Ecole Normale Supérieure, France
• Lisbeth Fajstrup, Aalborg University, Denmark
• Eric Goubault, Commissariat à l'Energie Atomique, France
• Maurice Herlihy, Brown University, Providence, RI, USA
• Kim G. Larsen, Aalborg University, Denmark
• Martin Raussen, Aalborg University, Denmark

Ulrich Fahrenberg
Department of Mathematical Sciences, Aalborg University
Fredrik Bajers Vej 7G
9220 Aalborg East

Phone: +45 96 35 88 00
Fax: +45 98 15 81 29
Email: uli@math.aau.dk