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The power graph of a group is the graph whose vertex set is the set of nontrivial elements of group, two elements being adjacent if one is a power of the other. We introduce some way for find the automorphism groups of some graphs. As an…

Group Theory · Mathematics 2019-02-15 Sayyed Heidar Jafari

The paper presents the complete classification of Automorphic Lie Algebras based on $\mathfrak{sl}_n (\mathbb{C})$, where the symmetry group $G$ is finite and the orbit is any of the exceptional $G$-orbits in $\overline{\mathbb{C}}$. A key…

Mathematical Physics · Physics 2019-11-20 Vincent Knibbeler , Sara Lombardo , Jan A. Sanders

We study automorphism groups of fibered surfaces for finite cyclic covering fibrations of an elliptic surface. We estimate the order of a finite subgroup of automorphism groups in terms of the genus of the fiber, the genus of the base…

Algebraic Geometry · Mathematics 2023-04-18 Hiroto Akaike

Let $X=G/H$ be a spherical homogeneous variety for a complex reductive algebraic group $G$. We prove that the orbit space of $X$ under the action of a maximal compact subgroup $K\subset G$ is homeomorphic to the valuation cone of $X$. We…

Algebraic Geometry · Mathematics 2025-11-12 Dmitry A. Timashev

We give upper bounds on the order of the automorphism group of a simple graph

Combinatorics · Mathematics 2007-05-23 Ilia Krasikov , Arie Lev , Bhalchandra D. Thatte

The group ring of the automorphism group of a p-group is studied using the automorphism groups of subgroups and quotient groups of P.

Representation Theory · Mathematics 2007-11-12 John Martino , Stewart Priddy

We consider the class of quasiprojective varieties admitting a dominant morphism onto a curve with negative Euler characteristic. The existence of such a morphism is a property of the fundamental group. We show that for a variety in this…

Algebraic Geometry · Mathematics 2007-05-23 T. Bandman , A. Libgober

The purpose of this paper is to propose an efficient method to compute the automorphism group of an arbitrary hyperelliptic function field (genus>1) over a given ground field of characteristic >2 as well as over its algebraic extensions.

Number Theory · Mathematics 2007-05-23 Norbert Goeb

We compute the mapping class group orbits in the homotopy set of framings of a compact connected oriented surface with non-empty boundary. In the case $g > 1$ the computation is some modification of Johnson's results and certain arguments…

Geometric Topology · Mathematics 2017-03-30 Nariya Kawazumi

Given an autohomeomorphism on an ordered topological space or its subspace, we show that it is sometimes possible to introduce a new topology-compatible order on that space so that the same map is monotonic with respect to the new ordering.…

General Topology · Mathematics 2023-06-27 Raushan Buzyakova

In this paper we will refine Sacksteder's theorem for groups of orientation-preserving homeomorphisms of the circle in the case that there exists a finite orbit set. We will give a categorization of the topological possibilities for the…

Dynamical Systems · Mathematics 2007-05-23 N. C. Esty

This is a biased survey for the Johnson homomorphisms of the automorphism groups of free groups. We just exposit some well known facts and recent developments for the Johnson homomorphisms and its related topics.

Algebraic Topology · Mathematics 2013-06-11 Takao Satoh

Orbits of coadjoint representations of classical compact Lie groups have a lot of applications. They appear in representation theory, geometrical quantization, theory of magnetism, quantum optics etc. As geometric objects the orbits were…

Representation Theory · Mathematics 2013-07-09 Julia Bernatska , Petro Holod

We present a construction for the holomorph of an inverse semigroup, derived from the cartesian closed structure of the category of ordered groupoids. We compare the holomorph with the monoid of mappings that preserve the ternary heap…

Group Theory · Mathematics 2014-02-20 N. D. Gilbert , E. A. McDougall

We realize the Apollonian group associated to an integral Apollonian circle packings, and some of its generalizations, as a group of automorphisms of an algebraic surface. Borrowing some results in the theory of orbit counting, we study the…

Algebraic Geometry · Mathematics 2014-09-03 Igor Dolgachev

We describe complete simplicial toric varieties on which a unipotent group acts with a finite number of orbits. We also provide a complete list of such varieties in the case where the dimension is equal to 2.

Algebraic Geometry · Mathematics 2025-08-05 Anton Shafarevich

We address a natural question in noncommutative geometry, namely the rigidity observed in many examples, whereby noncommutative spaces (or equivalently their coordinate algebras) have very few automorphisms by comparison with their…

Rings and Algebras · Mathematics 2022-04-29 Nicholas Cooney , Jan E. Grabowski

We provide an explicit characterization of the covariant isotropy group of any Grothendieck topos, i.e. the group of (extended) inner automorphisms of any sheaf over a small site. As a consequence, we obtain an explicit characterization of…

Category Theory · Mathematics 2021-04-29 Jason Parker

We compute the automorphism group of OT manifolds of simple type. We show that the graded pieces under a natural filtration are related to a certain ray class group of the underlying number field. This does not solve the open question…

Differential Geometry · Mathematics 2018-08-01 Oliver Braunling , Victor Vuletescu

We define a homomorphism from (a certain extension of) the fundamental group of the Hamiltonian automorphism group of a symplectic manifold to the group of invertibles in its quantum cohomology ring. The manifold must satify a technical…

dg-ga · Mathematics 2008-02-03 Paul Seidel