Dynamical and Topological Aspects of Lyapunov Graphs

Maria Alice Bertolim, Margarida Pinheiro Mello, Ketty Abaroa de Rezende

Dedicated to Professor Sotomayor 60th birthday

In this survey we present the interplay between topological dynamical systems theory with network flow theory in order to obtain a continuation result for abstract Lyapunov graphs $L(h_0, \ldots, h_n,\kappa)$ in dimension $n$ with cycle number $\kappa$. We also show that an abstract Lyapunov graph satisfies the Poincar\'{e}-Hopf inequalities if and only if it satisfies the Morse inequalities and the first Betti number $\gamma_1$ is greater than or equal to $\kappa$. We define the Morse polytope determined by the Morse inequalities and describe some of its geometrical properties.