论文标题
相对自由分裂复合物II:稳定的翻译长度和所有定理的两个
Relative Free Splitting Complexes II: Stable Translation Lengths and the Two Over All Theorem
论文作者
论文摘要
这是相对自由分裂复合物的三部分研究中的第二份$ \ Mathcal {fs}(γ; \ Mathscr a)$,从第〜i部分已知是Gromov双曲线。在此处和第三部分中,我们专注于稳定的翻译长度$τ_D\ ge 0 $ $ \ Mathcal {fs}(fs}(γ; \ mathscr a)$由相对外部自动形态引起的$ \ text \ in \ text {out}(γ;; \ m nation $ nitiatiate and and anditiated and s anditiated and and s and and s and s and sateers and sateers sate sate and sate sate sate and sate nip and temanccr {fs}(fs; \ mathscr a)$ $ \ text {out}(f_n)$。第〜II部分在此处证明的主要技术结果是\ emph {两个phos the theorem},它在$ \ mathcal {fs}(γ; \ mathscr a)$中表达沿任意失速折叠路径沿任意失速的折叠路径的均匀指数的flaring属性,即使对于$ \ \ text {out}(f_n)$。我们提供了该定理的两个应用。首先,来自相对外部空间的自然图$ {\ mathscr o}(γ; \ mathscr a)$到相对免费分裂复杂的$ \ MATHCAL {fs}(fs; \ mathscr a)$是log-lipschitz semimetric on〜$ $ {$ {$ {$ {$ o)的lig-lipschitz semimetric,是log-lipschitz semimetric oon lig-lipschitz的c.其次,如果$ ϕ \ in \ text {out}(γ; \ m mthscr a)$具有填充吸引的层压,则用膨胀因子$λ> 1 $ $ 1 $,则稳定的翻译长度$ ϕ $作用于$ \ nathcal {fs}(fs}}(γ; \ nathscr a)$具有上限的上限。
This is the second of a three part study of relative free splitting complexes $\mathcal{FS}(Γ;\mathscr A)$, known from Part~I to be Gromov hyperbolic. Here and in~Part III we focus on stable translation lengths $τ_ϕ\ge 0$ of the simplicial isometries of $\mathcal{FS}(Γ;\mathscr A)$ induced by relative outer automorphisms $ϕ\in \text{Out}(Γ;\mathscr A)$, stating and proving quantitative generalizations of earlier theorems for $\text{Out}(F_n)$. The main technical result proved here in Part~II is the \emph{Two Over All Theorem}, which expresses a uniform exponential flaring property along arbitrary Stallings fold paths in $\mathcal{FS}(Γ;\mathscr A)$, a new result even for $\text{Out}(F_n)$. We give two applications of this theorem. First, the natural map from the relative outer space ${\mathscr O}(Γ;\mathscr A)$ to the relative free splitting complex $\mathcal{FS}(Γ;\mathscr A)$ is coarsely Lipschitz, with respect to the log-Lipschitz semimetric on~${\mathscr O}(Γ;\mathscr A)$. Second, if $ϕ\in \text{Out}(Γ;\mathscr A)$ has a filling attracting lamination with expansion factor $λ>1$ then the stable translation length of $ϕ$ acting on $\mathcal{FS}(Γ;\mathscr A)$ has an upper bound of the form~$B \log(λ)$.