L'équipe ARITH du LIRMM a le plaisir de recevoir durant la semaine du 16 avril 2012 le professeur Erich Kaltofen de North Carolina State University (http://www4.ncsu.edu/~kaltofen/).

Durant cette visite, Erich Kaltofen nous proposera un exposé généraliste sur le calcul hybride symbolique/numérique.

L'exposé aura lieu le Jeudi 19 avril 2012 à 14h en salle 169 (St-Priest).


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Title: The Art of Hybrid Computation
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Abstract:

Hybrid symbolic-numeric computation constitutes the Fifth of my "Seven Dwarfs" of Symbolic Computation, which I have listed in my SNSC talk in Hagenberg in 2008.
Hybridization requires that the solution of a computational mathematical problem should utilize both a numeric and a symbolic algorithmic component.

In my talk, I will characterize the hybrid methodology by surveying some important results and the lessons I have learned from them.
Those include the notion of approximate GCD and approximate sparse interpolant, and the task of the analysis of the random distributions of matrix condition numbers
in randomized hybrid algorithms.

One can bypass the analysis by producing a certificate, and I will give sum-of-squares certificates in global optimization via our ArtinProver software.
Specifically, I will discuss certificates of impossibility of sum-of-squares representations based on the Farkas Lemma of semidefinite programming.

This work is in collaboration with Matthew Comer, Feng Guo, Wen-shin Lee, Clement Pernet, Zhengfeng Yang, and Lihong Zhi.


Contact : Pascal Giorgi