A Polynomial System from Differential Equations

Dongming Wang

Date: July 19th (Friday)
Time: 15:00-15:30
Abstract
For a class of cubic differential systems the necessary and sufficient conditions for the origin to be a center were derived by I. S. Kukles in 1944. These conditions were discovered to be incomplete in the later 1980s with the aid of elimination methods and computer algebra tools. Since then there have been several attempts to establish the complete conditions without success. The problem of completing the conditions can be reduced partially to decomposing a large system of polynomial equations, which can be done in principle by existing algorithms of polynomial elimination. However, the occurring polynomials are too large in terms of degree and number of terms to be manageable. Various techniques and software tools have been tried both automatically and interactively, but the complete conditions have never been obtained.

In this talk, we explain the initial problem, present the polynomial system generated by a program from Kukles' differential systems, report some of our experiments, and point out the major difficulties encountered in dealing with the system. The generated polynomial system and some of its subsystems will be made available electronically. We propose the problem of solving these systems as an open challenge for testing elimination algorithms and their implementations and call publicly for solutions from algorithm and software developers.

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