URGENT, arrival schedule


The organizers of the event got an agreement with the taxi drivers of the city of Cartagena, who will pick up participants at the airport and will transport them to the hotel at a special rate. At the same time we expect to have at the airport some people from the organization awaiting for participants and helping them with a safe and secure arrival to the hotel.

To make sure that this gets adecuately coordinated we are asking participants to send the arrival schedule to the e-mail:

Hotel reservation


The organization of CIMPA school is requesting each participant to confirm via e-mail
the dates in which you plan to participate in the event, this independent of whether
you have hotel reservation (Cartagena Plaza). Please send this information to the e-mail

Also, if you already have hotel reservation (Cartagena Plaza), please inform

Participants who have been assigned economical help from the school, the organizers of
the event will make the reservation.



We are pleased of informing about the new course taught by professor Dag Oskar Madsen 

Title: Extension algebras

Abstract:  Given an algebra Ë with Jacobson radical J, we study the Yoneda
extension algebra Ext*(Ë/J, Ë/J), both in a graded and ungraded setting. In
the graded setting we will be especially interested in the Koszul property.
We then cover the basics of quasi-hereditary algebras. For nice enough quasi-
hereditary algebras will look at the extension algebra of standard modules
Ext*(Ä, Ä) and observe Koszul-like phenomena there. The whole course will
focus on computations and examples.

Suggested preparatory reading:

D.J. Benson, Representations and cohomology I, sections 2.4-2.6.

D. Zacharia, Ext and Koszul algebras,

R. Farnsteiner, Quasi-hereditary algebras: homological properties,

immigration requirements of Colombia


For guests:

 1. We are going to send a letter of invitation by mail. This should be presented at immigration when entering Colombia at the desk were the passport is stamped. Please do not miss this step which is strictly necessary for us to be able to to legalize all the money allocated by the University of Antioquia for this visits.

 2. Participants who come from Brazil or other tropical countries, confirm if  they need the vaccine against yellow fever, this minimum must be applied 10  days before departure.



Dear participants of the Research School “Algebraic Structures, their representations and applications in geometry and non associative models”,

In order to complete your hotel reservations for the school, please take into account this mandatory restrictions:


1)      The official Hotel of the School is Cartagena Plaza (please see The CIMPA recommends that all participants are hosted in same hotel to promote scientific discussions between the lecturers and students beyond those in the lecture rooms. Besides that, the organizers have negotiated very attractive rates for the Cartagena Plaza Hotel on the basis that all participants are hosted in it, so it is mandatory that all participants are hosted in the official hotel during the School. The hotel in exchange will provide all the facilities of lecture rooms, coffee breaks, and allocations “all included”. This means, that it provides all the meals, snacks, and multiple very attractive hotel services.

2)      When you make the hotel reservation at the Cartagena Plaza you must indicate that you will attend the “CIMPA School” ( or “Escuela CIMPA”) in order to receive the benefits (discounts) of the special rates negotiated for the School.

3)      We need to receive information about your reservation dates and confirmations in order to try to coordinate the logistics of the participant’s arrivals and departures. Please be so kind to submit a copy of your reservation’s confirmations to the email address .  We want to verify that you receive the benefits of the rates negotiated for the School. With this information we will coordinate also the room assignments to those selecting non single rooms which are not filled by their own parties.  We will communicate to them to take into account their preferences.





Registration for all participants

The School will partially support some participants residing in Colombia
(registration fee / living expenses). In order to apply, please see

Participants outside of Colombia should also register at the CIMPA webpage.
They can also apply for funding there. Please see

Important Deadlines:


Deadline to request for financial help for stay and registration: December
18, 2011

Deadline for registration without support: February 3, 2012

Reception of talk proposals until January 10, 2012
Acceptance / Rejection until January 30, 2012



We are pleased of informing about the new course taught by professor Otmar Venjakob.

Title: p-adic numbers and the Hasse principle

Abstract: Hasse's local-global principle  is the idea that one can find an integer solution to an equation by using the Chinese emainder theorem to piece together solutions modulo powers of each different prime number. This is handled by examining the equation in the completions of the rational numbers: the real numbers and the p-adic numbers. A more formal version of the Hasse principle states that certain types of equations have a rational solution if and only if they have a solution in the real numbers and in the p-adic numbers for each prime p.

The aim of this course is to give firstly an introduction into p-adic numbers and analysis (different constructions of p-adic integers, ultrametric fields, Hensel's lemma, p-adic power seires) and secondly to apply them to study Diophantine equations. In particular we will sketch the proof of the local-global principles for quadratic forms, i.e., of the Hasse–Minkowski theorem,  and discuss a counter example for cubic forms.

Finally, we want to point out that  - while the above results are classical - p-adic methods still play  a crucial role in modern arithmetic geometry, i.e.,  in areas like p-adic Hodge theory, p-adic representation theory/p-adic local Langlands or Iwasawa theory.