Results 61 to 70 of about 118,465 (290)
Automorphism groups of Grassmann codes
We use a theorem of Chow (1949) on line-preserving bijections of Grassmannians to determine the automorphism group of Grassmann codes. Further, we analyze the automorphisms of the big cell of a Grassmannian and then use it to settle an open question of ...
Artin +24 more
core +2 more sources
HOMOMORPHISMS FROM AUTOMORPHISM GROUPS OF FREE GROUPS [PDF]
The automorphism group of a finitely generated free group is the normal closure of a single element of order 2. If $m$ is less than $n$ then a homomorphism $Aut(F_n)\to Aut(F_m)$ can have cardinality at most 2. More generally, this is true of homomorphisms from $\Aut(F_n)$ to any group that does not contain an isomorphic copy of the symmetric group $S_{
Bridson, MR, Vogtmann, K
openaire +4 more sources
AUTOMORPHISM GROUPS OF RANDOMIZED STRUCTURES [PDF]
We study automorphism groups of randomizations of separable structures, with focus on the ℵ0-categorical case. We give a description of the automorphism group of the Borel randomization in terms of the group of the original structure.
Tomás Ibarlucía
semanticscholar +1 more source
Automorphism group of certain power graphs of finite groups
The power graph $\mathcal{P}(G)$ of a group $G$ is the graphwith group elements as vertex set and two elements areadjacent if one is a power of the other. The aim of this paper is to compute the automorphism group of the power graph of several well-known
Ali Reza Ashrafi +2 more
doaj +1 more source
Residual properties of automorphism groups of (relatively) hyperbolic groups
We show that Out(G) is residually finite if G is a one-ended group that is hyperbolic relative to virtually polycyclic subgroups. More generally, if G is one-ended and hyperbolic relative to proper residually finite subgroups, the group of outer ...
Levitt, Gilbert, Minasyan, Ashot
core +3 more sources
Let \({\mathcal E}\colon N\rightarrowtail G\twoheadrightarrow Q\) be a group extension with coupling \(\chi\colon Q\to\text{Out\,}N\). If \(\Aut\,{\mathcal E}=\{\gamma\in\Aut\,G\mid N^\gamma=N\}\), \(\text{Comp}(\chi)\) the group of all compatible pairs for \(\chi\) and \(A\) the center of \(N\) regarded as a \(Q\)-module via \(\chi\) then it is known [
openaire +2 more sources
On Groups in Which Many Automorphisms Are Cyclic
Let G be a group. An automorphism α of G is said to be a cyclic automorphism if the subgroup ⟨x,xα⟩ is cyclic for every element x of G. In [F. de Giovanni, M.L. Newell, A. Russo: On a class of normal endomorphisms of groups, J.
Mattia Brescia, Alessio Russo
doaj +1 more source
Homology stability for outer automorphism groups of free groups
We prove that the quotient map from Aut(F_n) to Out(F_n) induces an isomorphism on homology in dimension i for n at least 2i+4. This corrects an earlier proof by the first author and significantly improves the stability range. In the course of the proof,
Allen Hatcher +4 more
core +2 more sources
The automorphism group of Hall’s universal group [PDF]
We study the automorphism group of Hall's universal locally finite group $H$. We show that in $Aut(H)$ every subgroup of index $< 2^ $ lies between the pointwise and the setwise stabilizer of a unique finite subgroup $A$ of $H$, and use this to prove that $Aut(H)$ is complete.
Paolini, G., & Shelah, S.
openaire +5 more sources
Computing automorphism groups of shifts using atypical equivalence classes
Computing automorphism groups of shifts, using atypical equivalence classes, Discrete Analysis 2016:3, 24 pp. Symbolic dynamics is about dynamical systems of the following type.
Ethan Coven, Anthony Quas, Reem Yassawi
doaj +1 more source

