The Ruell inequality of folding type and its application for interval or circle maps
摘要：In dynamical systems, the classical Ruelle inequality tells us that the metric entropy is dominated by the sum of positive Lyapunov exponents. In this talk, a folding type Ruelle inequality is discussed, which looks at the system from backward process. Then as an application of this inequality, we introduce the notion of folding rate and discuss upper semi-continuity of metric entropy for C^r(r>1) interval (or circle) maps. This is a joint work with Gang Liao.