NORTHEASTERN U NIVERSITY
MATHEMATICS D EPARTMENT


Geometry-Algebra-Singularities-Combinatorics 
Seminar


Equisigularity of sections, t^r conditions and the integral closure of modules

   

Leslie Wilson

(University of Hawaii)

 

Northeastern University

511 Lake Hall

1:30 p.m., Monday, Ocrtober 28, 2002


Abstract: (with Gaffney and Trotman) This paper will examine the $t^r$ conditions which were introduced by Thom and Trotman, which concern families of $C^r$ sections of a singular set.  For real and complex  analytic sets, we show that the $t^r$0 conditions have algebraic formulations in terms of integral closure of  modules.

Our formulation gives a new simple proof, for analytic sets, of the change in the conditions under Grassmann modification proved by Kuo and Trotman for subanalytic sets; this is used in conjuntion with the principle of specializtion of integral dependence to give numerical criteria for families of plane sections of complex  complete intersections to be Whitney equisingular.