Results 81 to 90 of about 30,795 (238)
Exotic torus manifolds and equivariant smooth structures on quasitoric manifolds
In 2006 Masuda and Suh asked if two compact non-singular toric varieties having isomorphic cohomology rings are homeomorphic. In the first part of this paper we discuss this question for topological generalizations of toric varieties, so-called torus ...
A. Fomenko +17 more
core +1 more source
Exact local distribution of the absolutely continuous spectral measure
Abstract It is well‐established that the spectral measure for one‐frequency Schrödinger operators with Diophantine frequencies exhibits optimal 1/2$1/2$‐Hölder continuity within the absolutely continuous spectrum (Avila and Jitomirskaya, Commun. Math. Phys. 301 (2011), 563–581).
Xianzhe Li, Jiangong You, Qi Zhou
wiley +1 more source
Twisted Burnside-Frobenius theory for endomorphisms of polycyclic groups
Let $R(\phi)$ be the number of $\phi$-conjugacy (or Reidemeister) classes of an endomorphism $\phi$ of a group $G$. We prove for several classes of groups (including polycyclic) that the number $R(\phi)$ is equal to the number of fixed points of the ...
Fel'shtyn, Alexander, Troitsky, Evgenij
core +1 more source
Simple 3‐Designs of PSL ( 2 , 2 n ) With Block Size 13
ABSTRACT This paper focuses on the investigation of simple 3‐( 2 n + 1 , 13 , λ ) designs admitting PSL ( 2 , 2 n ) as an automorphism group. Such designs arise from the orbits of 13‐element subsets under the action of PSL ( 2 , 2 n ) on the projective line X = GF ( 2 n ) ∪ { ∞ }, and any union of these orbits also forms a 3‐design.
Takara Kondo, Yuto Nogata
wiley +1 more source
Some designs and codes from L_2(q) [PDF]
For $q \in \{7,8,9,11,13,16\}$, we consider the primitive actions of $L_2(q)$ and use Key-Moori Method 1 as described in [Codes, designs and graphs from the Janko groups {$J_1$} and {$J_2$}, {\em J. Combin. Math. Combin.
Jamshid Moori +1 more
doaj
On universal‐homogeneous hyperbolic graphs and spaces and their isometry groups
Abstract The Urysohn space is the unique separable metric space that is universal and homogeneous for finite metric spaces, that is, it embeds any finite metric space any isometry between finite subspaces extends to an isometry of the whole space. We here consider the existence of a universal‐homogeneous hyperbolic space. We show that for δ>0$\delta >0$
Katrin Tent
wiley +1 more source
Fixed‐point posets of groups and Euler characteristics
Abstract Suppose that G$G$ is a group and Ω$\Omega$ is a G$G$‐set. For X$\mathcal {X}$ a set of subgroups of G$G$, we introduce the fixed‐point poset XΩ$\mathcal {X}_{\Omega }$. A variety of results concerning XΩ$\mathcal {X}_{\Omega }$ are proved as, for example, in the case when p$p$ is a prime and X$\mathcal {X}$ is a non‐empty set of finite non ...
Peter Rowley
wiley +1 more source
Groups with conjugacy classes of coprime sizes
Abstract Suppose that x$x$, y$y$ are elements of a finite group G$G$ lying in conjugacy classes of coprime sizes. We prove that ⟨xG⟩∩⟨yG⟩$\langle x^G \rangle \cap \langle y^G \rangle$ is an abelian normal subgroup of G$G$ and, as a consequence, that if x$x$ and y$y$ are π$\pi$‐regular elements for some set of primes π$\pi$, then xGyG$x^G y^G$ is a π ...
R. D. Camina +8 more
wiley +1 more source
Quasi‐Fuchsian flows and the coupled vortex equations
Abstract We provide an alternative construction of the quasi‐Fuchsian flows introduced by Ghys. Our approach is based on the coupled vortex equations that allows to see these flows as thermostats on the unit tangent bundle of the Blaschke metric, uniquely determined by a conformal class and a holomorphic quadratic differential.
Mihajlo Cekić, Gabriel P. Paternain
wiley +1 more source
Linear Diophantine equations and conjugator length in 2‐step nilpotent groups
Abstract We establish upper bounds on the lengths of minimal conjugators in 2‐step nilpotent groups. These bounds exploit the existence of small integral solutions to systems of linear Diophantine equations. We prove that in some cases these bounds are sharp.
M. R. Bridson, T. R. Riley
wiley +1 more source

