2002

February 8, Leiden (UL), Room 174.

10:30-11:30	J. Hancl, Irrationality and transcendence of series of rational numbers
11:45-12:45	Jan-Hendrik Evertse, Multivariate Diophantine equations with many solutions

The building will close at 13:00 because of the "Dies". At 15:00 an honorary doctorate will be given to H. Brezis in the Pieterskerk in Leiden

March 8, Utrecht, Room K11

13:00-14:45	Gunther Cornelissen, Diophantine sets and abelian varieties.
15:00-16:45	Frits Beukers, Factorisation on a quantum computer

March 22, Groningen, Room RC 59

11:45 - 12:30	Jaap Top,Introduction to Drinfeld modules
13:15 - 15:00	Gert-Jan van der Heiden, A local-global problem for elliptic curves and Drinfeld modules
15:15 - 17:00	Lenny Taelman, Moduli of Drinfeld modules

April 4, Eindhoven

At the first of the two days of the Nederlands Mathematisch Congres the bi-annual Beeger lecture will be given by Bjorn Poonen. In the afternoon there will be a number theory session "Minisymposium getaltheorie" organised by Peter Stevenhagen and Rob Tijdeman.

11:45-12:45	Bjorn Poonen Beeger lecture
13:45-14:15	Bart de Smit
14:20-14:50	Pieter Moree
14:55-15:25	Johnny Edwards

April 26, VU Amsterdam, Room N343 (route)

11:00-12:00	Lenny Taelman, Lie symmetries and Galois groups of linear differential equations
12:15-12:45 & 13:30-14:00	Jaap Top, Introduction to (generalized) symmetries of evolution equations
14:15-15:15	Peter van der Kamp Classifying integrable systems using number theory

May 17, Eindhoven (TUE, route), HG 6.09

11:30-12:15	Andries Brouwer, Introduction to Lie algebras Abstract: Definition of Lie algebras and root systems, and the classification of split (semi-)simple Lie algebras in characteristic 0.
13:15-14:00	Willem de Graaf, Constructing homomorphisms between Verma modules Abstract: Fix a Borel subalgebra b of a simple Lie algebra g. Then g-modules induced from irreducible b-modules are called Verma modules of g. The space of homomorphisms between two Verma modules (w.r.t. the same b) is at most one-dimensional, and any such homomorphism which is non-zero is in fact injective. Hence, there is a natural notion of inclusion among Verma modules. This talk describes how to implement Verma modules in GAP, and how to compute explicitly the non-zero homomorphisms among them.
14:15-15:00	Don Taylor, Computations in semisimple algebraic groups Abstract: Semisimple algebraic groups are closely related to semisimple Lie algebras. In particular, the root systems classifying the latter give rise to a normal form of elements of the former: the so-called Steinberg presentation. This raises various computational questions, such as: how to find the Steinberg presentation of an element of a semisimple algebraic group, which is given by its matrix in some representation of that group?
15:15-16:00	Jan Draisma, The adjoint representation of certain Lie algebras of polynomial vector fields Abstract: The action of a complex simple algebraic group G on a homogeneous space G/P where P is a parabolic subgroup with Abelian unipotent radical gives rise to an action of the Lie algebra g of G by vector fields on some open dense part U of G/P. The Lie algebra D of all vector fields on U can thus be viewed as a g-module, the action being given by the commutator. As such, D turns out to have a beatiful structure; for example, its composition factors seem to be parameterized by certain double cosets in the Weyl group of g.

May 31, Leiden, Room 174

11:30-12:15	Tom Schmidt, Galois orbits of congruence curves defined by nonarithmetic groups
12:30-13:15	Robert Carls, Counting points by a method of Mestre
14:15-15:00	Stefania Cavallar, On the Three-Large-Primes Variant of the Number Field Sieve
15:15-16:00	Christiaan van de Woestijne, Quadratic Forms over Finite Fields
16:15-17:00	Reinier Bröker, The Hopf-algebroid of formal grouplaws

Fall 2002