论文标题
在$ sl(2,\ mathbb {r})$ - 与次级碰撞的非理性旋转上
On $SL(2,\mathbb{R})$-cocycles over irrational rotations with secondary collisions
论文作者
论文摘要
我们考虑一个偏斜的产品$ f_ {a} =(σ_为,a)$在非理性旋转上$σ_Ω(x)= x +ω$的circle $ \ mathbb {t}^{1} $。据认为,转换$ a:\ mathbb {t}^{1} \ to sl(2,\ mathbb {r})$是a $ c^{1} $ - 地图具有form $ a(x)= r(x)= r(φ(x))z(λ(λ))$ r(λ(λ))$ a $ r(φ)角度$φ$和$ z(λ)= diag \ {λ,λ^{ - 1} \} $是对角矩阵。假设$λ(x)\geλ_{0}> 1 $具有足够大的常数$λ_{0} $,并且函数$φ$使得$ \cosφ(x)$仅具有简单的零,我们研究由$ f_ {a} $生成的同伴生成的双曲线属性。我们采用关键集合方法来表明,在功能$φ$的衍生产品的一些其他要求下,二次碰撞补偿了由于主要碰撞而导致的双曲线的弱化,而$ f_ {a} $产生的合子碰撞与二次碰撞可能被部分消除相反。
We consider a skew product $F_{A} = (σ_ω, A)$ over irrational rotation $σ_ω(x) = x + ω$ of a circle $\mathbb{T}^{1}$. It is supposed that the transformation $A: \mathbb{T}^{1} \to SL(2, \mathbb{R})$ being a $C^{1}$-map has the form $A(x) = R(φ(x)) Z(λ(x))$, where $R(φ)$ is a rotation in $\mathbb{R}^{2}$ over the angle $φ$ and $Z(λ)= diag\{λ, λ^{-1}\}$ is a diagonal matrix. Assuming that $λ(x) \ge λ_{0} > 1$ with a sufficiently large constant $λ_{0}$ and the function $φ$ be such that $\cos φ(x)$ possesses only simple zeroes, we study hyperbolic properties of the cocycle generated by $F_{A}$. We apply the critical set method to show that, under some additional requirements on the derivative of the function $φ$, the secondary collisions compensate weakening of the hyperbolicity due to primary collisions and the cocycle generated by $F_{A}$ becomes hyperbolic in contrary to the case when secondary collisions can be partially eliminated.