Abstract:

The Lev Ginzburg system of differential equations is a model of population dynamics and it is given by (dx/dt,dy/dt)=(y,(1-by)(c-ax+dy)). In this talk we will discuss about the existence of limit cycles for this system. Moreover, we will give an example to show that the hypothesis that the neighborhood is bounded is essential in the Theorem of Averaging via Brouwer degree.

This is a joint work with Rodrigo Euzebio (UNESP/Brazil), Luis Fernando Mello (UNIFEI/Brazil) and Jaume Llibre (UAB/Spain).