天元讲堂（7.14） 张金华博士报告
报告人 张金华（北京大学）
报告时间 2017年7月14日09:30-10:30
报告地点 维格堂319
报告摘要 In this talk, we will show that given a pair of transverse $C^1$ foliations (F,G) on the torus, one can find a non-trivial loop in Diff^1(T^2) such that this loop acts on the foliation F and keeps the transversality with G. The proof uses very fundamental topological tools. As an application, we build new partially hyperbolic diffeomorphisms on 3-manifolds. This result is a sequel to a result of Bonatti-Pawarni-Potrie. The novelty of such examples is that they are not leaf conjugate to any of the classical models on 3-manifolds. This is a joint work with Christian Bonatti.
报告题目：Partially hyperbolic diffeomorphisms with one-dimensional neutral center
报告人 张金华（北京大学）
报告时间 2017年7月14日10:30-11:30
报告地点 维格堂319
报告摘要 A partially hyperbolic diffeomorphism f on a 3-manifold M has neutral center, if there exists c>1 such that
1/c<|Df^n|_E^c(x)|<c, for any x ∈ M and any integer n ∈Z.
For such diffeomorphism, it is always dynamically coherent, this is due to F. Rodriguez Hertz, J. Rodriguez Hertz and R. Ures.
In this talk, we will show that for such diffeomorphisms, the center stable and center unstable foliations are complete. Moreover, each leaf of center stable or center unstable foliation is a plane, a Mobius band or a cylinder.