اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدThickness of $mathsf{Out}(A_1*...*A_n)$
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تأليف
Saikat Das
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In this paper we have examined hyperbolicity and relative hyperbolicity of $Gamma_n := mathsf{Out}(G_n)$ , where $G_n = A_1*...*A_n$, is a finite free product and each $A_i$ is a finite group. We have used the $mathsf{Out}(G_n)$ action on the Guirardel-Levitt deformation space, to find a virtual generating set and prove quasi isometric embedding of a large class of subgroups. We have used ideas from works of Mosher-Handel and Alibegovic to prove non-distortion. We have used these subgroups to prove that $Gamma_n$ is thick for higher complexities. Thickness was developed by Behrstock-Druc{t}u-Mosher and thickness implies that the groups are non-relatively hyperbolic.
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S. Gersten announced an algorithm that takes as input two finite sequences $vec K=(K_1,dots, K_N)$ and $vec K=(K_1,dots, K_N)$ of conjugacy classes of finitely generated subgroups of $F_n$ and outputs: (1) $mathsf{YES}$ or $mathsf{NO}$ depending on
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