Woensdag 26 januari 2005
Spreker: 
Shigeru Kuroda (Kyoto)

Titel: 
The kernel of a derivation and the fourteenth problem of Hilbert

Tijd: 
11:00  12:00

Plaats: 
CK N4 (N3045)

Vanaf half 11 is er koffie en chocola in de Weylkamer
(N2046).
Abstract
Although the fourteenth problem of Hilbert itself has already been settled
negatively in the 1950s, the answers in some special cases still have not been
known.
In this talk, we will first give counterexamples to the problem in some of these
unsolved cases, then explain a general method for constructing counterexamples.
We make use of the derivations of a polynomial ring.
By using our construction, various counterexamples can be obtained
systematically.
Finally, as a simple application of our theory, we give a sufficient condition
on triangular derivations to have infinitely generated kernels.