Prof. Wolfgang Metzler (Frankfurt)
26/2/02, ore 17:30, Sala dei Seminari

	    "On the present status of the 
	generalized Andrews-Curtis conjecture"

(joint with Cynthia Hog-Angeloni)

Abstract:  Since a couple of years we deal with the Andrews-Curtis
problem for nontrivial fundamental groups and with fixed
subcomplexes. We exhibited potential counterexamples and also
detected a method of studying certain iterated semidirect products
of locally indicable groups which look very promising in actually
establishing a distinguishing invariant via tests to show that
certain infinite families of perfect groups contain only
nontrivial members. Based on a result of J. Howie and H. R.  
Schneebeli, Manuscripta math. 44 (1983), which deals with
solutions of systems of equations over group rings of such groups,
we were able to show that certain families of these equations have
non-trivial solutions.