Search results for "Automorphisme"
showing 3 items of 3 documents
From resurgent functions to real resummation through combinatorial Hopf algebras
2014
Pas de résumé en anglais.
Embeddings of Danielewski hypersurfaces
2008
In this thesis, we study a class of hypersurfaces in $\mathbb{C}^3$, called \emph{Danielewski hypersurfaces}. This means hypersurfaces $X_{Q,n}$ defined by an equation of the form $x^ny=Q(x,z)$ with $n\in\mathbb{N}_{\geq1}$ and $\deg_z(Q(x,z))\geq2$. We give their complete classification, up to isomorphism, and up to equivalence via an automorphism of $\mathbb{C}^3$. In order to do that, we introduce the notion of standard form and show that every Danielewski hypersurface is isomorphic (by an algorithmic procedure) to a Danielewski hypersurface in standard form. This terminology is relevant since every isomorphism between two standard forms can be extended to an automorphism of the ambiant …
Automorphisms of right-angled Artin groups
2012
The purpose of this thesis is to study the automorphisms of right-angled Artin groups. Given a finite simplicial graph $\Gamma$, the right-angled Artin group $G_\Gamma$ associated to $\Gamma$ is the group defined by the presentation whose generators are the vertices of $\Gamma$, and whose relators are commutators of pairs of adjacent vertices. The first chapter is intended as a general introduction to the theory of right-angled Artin groups and their automorphisms. In a second chapter, we prove that every subnormal subgroup of $p$-power index in a right-angled Artin group is conjugacy $p$-separable. As an application, we prove that every right-angled Artin group is conjugacy separable in th…