Abstract by Prof. Jesus A. de Loera

Hilbert's 16th Problem and a Combinatorial Construction of Viro.
Hilbert's 16th problem is concerned with the classification of topological types of smooth real projective hypersurfaces. It is clearly important to have available effective methods to produce examples of new topological types. During the 1980's Oleg Viro developed a combinatorial technique for constructing hypersurfaces with given topology. This technique has been highly succesful and was used by Ilia Itenberg, in 1993, to provide counterexamples to the longstanding Ragsdale conjecture.

Viro's construction of real smooth hypersurfaces uses regular (also called convex or coherent) triangulations of Newton Polytopes. Nevertheless, Viro's construction can be applied as well to arbitrary triangulations. Are the combinatorial hypersurfaces coming from non-regular triangulations, still topological types of real smooth hypersurfaces? In this talk we present an introduction to Viro's construction and the current advances toward the solution of the above question. As part of our efforts we have written software that allowed us to automatically generate Viro's surfaces and curves and compute their topological type. During the talk we will discuss the possibility of using computers for the investigation of Hilbert 16th problem. This is joint work with Frederick Wicklin (University of Minnesota).

Thursday - March 13, 1997.
4:00 PM - 314 Altgeld Hall - MATHEMATICS COLLOQUIUM
Coffee and tea will be offered before the talk in 321 Altgeld Hall at 3:15 PM.