混合双曲性：遍历性质和分叉现象（一种利用双曲性的方法）
Mingled hyperbolicities: ergodic properties and bifurcation phenomena (an approach using concavity)
摘要：
我们考虑了具有凹区间纤维映射的斜积映射，其子移位是轨道在给定区域的投影。它产生了一种新的（本质上）编码移位。纤维映射具有动态交互的扩展和收缩区域。动力学还表现出对马蹄铁的不同类型的双曲性，在某些情况下，是循环相关的。基上的遍历测度空间是一个熵稠密的Poulsen单形。这些测度正则地提升为斜积的遍历测度。我们解释何时以及如何空间（纤维）收缩和膨胀遍历措施胶沿非双曲的。一个关键的步骤是近似（在弱$\ast$拓扑和熵）的非双曲的措施遍历的，只获得通过的方法。凹性不仅是一种技术上的人工假设，而且它阻止了额外的独立子系统的存在。同宿关系的描述也是一个关键工具。这些斜积被嵌入在非减熵单参数族的自同构中，这些自同构从异维循环延伸到同宿类的碰撞。相关的分歧现象涉及遍历测度空间的跳跃，在某些情况下，还涉及熵的跳跃。
英文摘要：
We consider skew-products with concave interval fiber maps over a certain subshift obtained as the projection of orbits staying in a given region. It generates a new type of (essentially) coded shift. The fiber maps have expanding and contracting regions which dynamically interact. The dynamics also exhibits pairs of horseshoes of different type of hyperbolicity which, in some cases, are cyclically related. The space of ergodic measures on the base is an entropy-dense Poulsen simplex. Those measures lift canonically to ergodic measures for the skew-product. We explain when and how the spaces of (fiber) contracting and expanding ergodic measures glue along the nonhyperbolic ones. A key step is the approximation (in the weak$\ast$ topology and in entropy) of nonhyperbolic measures by ergodic ones, obtained only by means of concavity. Concavity is not merely a technical artificial hypothesis, but it prevents the presence of additional independent subsystems. The description of homoclinic relations is also a key instrument. These skew-products are embedded in non-decreasing entropy one-parameter family of diffeomorphisms stretching from a heterodimensional cycle to a collision of homoclinic classes. Associated bifurcation phenomena involve a jump of the space of ergodic measures and, in some cases, of entropy.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
