The entropy conjecture for diffeomorphisms away from tangencies
- Gang LiaoPeking University, Beijing, China
- Marcelo VianaIMPA - Instituto Nacional de Matemática Pura e Aplicada, Rio de Janeiro, Brazil
- Jiagang YangUniversidade Federal Fluminense - UFF, Niterói, Brazil

Abstract
We prove that every diffeomorphism away from homoclinic tangencies is entropy expansive, with locally uniform expansivity constant. Consequently, such diffeomorphisms satisfy Shub's entropy conjecture: the entropy is bounded from below by the spectral radius in homology. Moreover, they admit principal symbolic extensions, and the topological entropy and metrical entropy vary continuously with the map. In contrast, generic diffeomorphisms with persistent tangencies are not entropy expansive.
Cite this article
Gang Liao, Marcelo Viana, Jiagang Yang, The entropy conjecture for diffeomorphisms away from tangencies. J. Eur. Math. Soc. 15 (2013), no. 6, pp. 2043–2060
DOI 10.4171/JEMS/413