Results 51 to 60 of about 66,912 (209)

HOMOMORPHISMS FROM AUTOMORPHISM GROUPS OF FREE GROUPS [PDF]

Bulletin of the London Mathematical Society, 2003
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

Noncommutative polygonal cluster algebras

Journal of the London Mathematical Society, Volume 113, Issue 4, April 2026.
Abstract We define a new family of noncommutative generalizations of cluster algebras called polygonal cluster algebras. These algebras generalize the noncommutative surfaces of Berenstein–Retakh, and are inspired by the emerging theory of Θ$\Theta$‐positivity for the groups Spin(p,q)$\mathrm{Spin}(p,q)$.
Zachary Greenberg, Dani Kaufman, Merik Niemeyer, Anna Wienhard   +3 more
wiley   +1 more source

Relative outer automorphisms of free groups [PDF]

, 2011
Let $A_1,...,A_k$ be a system of free factors of $F_n$. The group of relative automorphisms $Aut(F_n;A_1,...,A_k)$ is the group given by the automorphisms of $F_n$ that restricted to each $A_i$ are conjugations by elements in $F_n$. The group of relative
Meucci, Erika
core  

Birational automorphisms of a three-dimensional double quadric with an elementary singularity

, 1998
It is proved that the group of birational automorphisms of a three-dimensional double quadric with a singular point arising from a double point on the branch divisor is a semidirect product of the free group generated by birational involutions of a ...
A. V. Pukhlikov, A. V. Pukhlikov, A. V. Pukhlikov, A. V. Pukhlikov, A. V. Pukhlikov, M M Grinenko, V. A. Iskovskikh, V. A. Iskovskikh, V. A. Iskovskikh, V. A. Iskovskikh   +9 more
core   +1 more source

Automorphism groups of 2-groups

Journal of Algebra, 2006
It is conjectured that \(|G|\mid|\Aut(G)|\) for every nonabelian \(p\)-group \(G\). In this paper the following results are proven. Theorem. For every \(s\in\mathbb{N}\) there exists \(o(r,s)\in\mathbb{N}\) such that \(2^s\mid|G|\mid|\Aut(G)|\) for all \(2\)-groups \(G\) of coclass \(r\) and order at least \(o(r,s)\). -- Corollary.
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Automorphism Groups of Abelian p-Groups [PDF]

Proceedings of the American Mathematical Society, 1975
Let r be the automorphism group of a nonelementary reduced abelian p-group, p > 5. It is shown that every noncentral norinal subgroup of r contains a noncentral elementary abelian normal p-subgroup of r of rank at least 2. 1. The result. Throughout the following, G is a reduced p-primary abelian group, p > 5, and F is the group of all automorphisms of ...
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Graphical small cancellation and hyperfiniteness of boundary actions

Journal of the London Mathematical Society, Volume 113, Issue 4, April 2026.
Abstract We study actions of (infinitely presented) graphical small cancellation groups on the Gromov boundaries of their coned‐off Cayley graphs. We show that a class of graphical small cancellation groups, including (infinitely presented) classical small cancellation groups, admit hyperfinite boundary actions, more precisely, the orbit equivalence ...
Chris Karpinski, Damian Osajda, Koichi Oyakawa   +2 more
wiley   +1 more source

Skein theory for the Links–Gould polynomial

Journal of the London Mathematical Society, Volume 113, Issue 4, April 2026.
Abstract Building further on work of Marin and Wagner, we give a cubic braid‐type skein theory of the Links–Gould polynomial invariant of oriented links and prove that it can be used to evaluate any oriented link, adding this polynomial to the list of polynomial invariants that can be computed by skein theory. As a consequence, we prove that this skein
Stavros Garoufalidis, Matthew Harper, Rinat Kashaev, Ben‐Michael Kohli, Jiebo Song, Guillaume Tahar   +5 more
wiley   +1 more source

The conjugacy problem for $\operatorname {Out}(F_3)$

Forum of Mathematics, Sigma
We present a solution to the conjugacy problem in the group of outer automorphisms of $F_3$ , a free group of rank 3. We distinguish according to several computable invariants, such as irreducibility, subgroups of polynomial growth and subgroups ...
François Dahmani, Stefano Francaviglia, Armando Martino, Nicholas Touikan   +3 more
doaj   +1 more source

Endomorphisms and automorphisms of locally covariant quantum field theories

, 2013
In the framework of locally covariant quantum field theory, a theory is described as a functor from a category of spacetimes to a category of *-algebras.
Buchholz D., CHRISTOPHER J. FEWSTER, Mac Lane S., Reed M., Takesaki M., Weyl H.   +5 more
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