Algebraic, Topological and Complexity
Aspects of Graph Covers

ATCAGC 2010 Workshop
Auckland, New Zealand, 15-19 February 2010

Overview : Venue : Participants : Schedule : Travel : Accommodation : Registration : Organisers : Other info : Other meetings


This research workshop will focus on graph coverings and their applications in different areas of mathematics such as algebraic graph theory, models of computation, and computational complexity. The aim is to bring together researchers working on these diverse ends of graph coverings, to introduce their approaches and results to one another, and to try to continue joint research in and between these fields. To achieve this we plan to have a small number of survey talks, several open problem sessions, and ample time for discussions and problem solving.

This is the second workshop in ATCAGC series; the first was held in February 2009 in Finse, Norway.


The ATCAGC 2010 Workshop will be held at the University of Auckland, which is located in the centre of Auckland, New Zealand, the week 15-19 February 2010. The weather in Auckland in February is usually excellent - the best part of New Zealand's summer - with temperatures between 22 and 27 degrees C most days, and little rain.

All the workshop sessions will be held in Room 279, Computer Science Department, Building 303 Extension, which is on the corner of Princes St and Wellesley St. For reference, here is a campus map (pdf 1.2MB).


Here is a list of main participants:


The likely schedule is given below. Click here for abstracts (in a pdf file).

Monday 15 February
  09:30-10:20 Aleksander Malnic: Let's lift an automorphism, shall we?
  10:30-11:00 Coffee/tea
  11:00-11:50 Martin Skoviera: Branched coverings of maps and voltage assignments
  12:00-14:00 Lunch break
  14:00-14:50 Roman Nedela: Graphs with semiedges and their coverings
  15:00-15:30 Coffee/tea
  15:30-16:45 Problem session 1
  17:30-19:00 Drinks party (at Staff Club, Old Government House)

Tuesday 16 February
  09:30-10:10 Jan Kratochvil: Computational Complexity of Graph Covers: The Never Ending Story Part II
  10:15-10:40 Jiri Fiala: Computational Complexity of Local Injective Homomorphisms: Why Lists Help
  10:45-11:15 Coffee/tea
  11:15-11:40 Marek Tesar: Locally injective homomorphisms to Theta graphs
  11:45-12:10 Bernard Lidicky: Computational Complexity of LIHomomorphisms to Weight Graphs
  12:15-14:00 Lunch break
  14:00-14:40 Milagros Izquierdo: Coverings of Riemann and Klein surfaces
  14:45-16:00 Break for Maths Dept Colloquium "What is Quantum Field Theory?"
                      David Brydges, University of British Columbia
                      [3pm to 4pm, in Engineering 3402, at 20 Symonds St]
  16:00-16:30 Coffee/tea
  16:30-17:00 Martin Macaj: Strongly regular graphs from coverings?

Wednesday 17 February
  [Free day - no particular events scheduled]

Thursday 18 February
  09:30-10:10 Primoz Potocnik: Census of tetravalent arc-transitive graphs
  10:15-10:40 Gabriel Verret: On tetravalent arc-transitive graphs with large vertex-stabilisers
  10:45-11:15 Coffee/tea
  11:15-11:40 Gabino Gonzalez-Diez: Dessins d'enfants, Riemann surfaces and covers
  11:45-12:10 Robert Jajcay: On the use of generalized truncation and anti-truncation in cage constructions
  12:15-14:00 Lunch break
  14:00-14:40 Mike Fellows: Algorithmic issues of operators on ideals
  14:45-15:15 Coffee/tea
  15:15-16:15 Jaroslav Nesetril: On the algebraic properties of graphs and homomorphisms between them
                      [Special 50-minute colloquium-style lecture]
  16:30-17:30 Problem session 2
  19:00-         Dinner (at Wagamama, 1 Courthouse Lane, Auckland)

Friday 19 February
  09:30-09:55 Marston Conder: Graph and surface coverings via combinatorial group theory
  10:00-10:25 Space for another talk (e.g. answers to problems from problem session)
  10:30-11:00 Coffee/tea
  11:00-12:00 Wrap-up, and discussion of next workshop?
  12:00           Workshop ends


If you are visiting from overseas, you might or might need a visa to enter New Zealand. See visa-free countries for more details.

If you are visiting from overseas, you might like to check the airfares available through APX Travel, the University of Auckland's travel supplier, which can issue airline tickets.

For transport from the Auckland airport to Auckland's central business district (CBD), which is where the University of Auckland is located, you have several options, all of which depart from just outside the airport:


Participants should organise their own accommodation. There are several possibilities:


If you wish to participate in this workshop, then please contact one of the organisers, or fill in your details below and click on the "Submit" button.

Your name

Your affiliation/institution

Your email address

Unless numbers of participants get too large, there will be no registration fee for this workshop.


Other info

See the 4ICC website (from December 2008) for other information on

Other meetings

Here's a list of other meetings on related topics or taking place at times close to this one:

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