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A connected graph $\Gamma$ of diameter ${\rm diam}(\Gamma) \ge \ell$ is $\ell$-distance-balanced if $|W_{xy}(\Gamma)|=|W_{yx}(\Gamma)|$ for every $x,y\in V(\Gamma)$ with $d_{\Gamma}(x,y)=\ell$, where $W_{xy}(\Gamma)$ is the set of vertices…

Combinatorics · Mathematics 2024-12-30 Gang Ma , Jianfeng Wang , Guang Li , Sandi Klavžar

In this paper we restrict ourselves to the particular case where the pseudogroup is $\Gamma \ltimes G$ given by the action of a dense subgroup $\Gamma$ of a Lie group $G$ acting on $G$ by left translations. For a Riemannian foliation $F$ on…

Algebraic Topology · Mathematics 2017-06-07 Andre Haefliger , Ana Maria Porto F. Silva

We define $G$-cospectrality of two $G$-gain graphs $(\Gamma,\psi)$ and $(\Gamma',\psi')$, proving that it is a switching isomorphism invariant. When $G$ is a finite group, we prove that $G$-cospectrality is equivalent to cospectrality with…

Combinatorics · Mathematics 2022-06-13 Matteo Cavaleri , Alfredo Donno

Let $X$ be a globally symmetric space of noncompact type, and $\Gamma\subset\Isom(X)$ a Schottky group of axial isometries. Then $M:=X/\Gamma$ is a locally symmetric Riemannian manifold of infinite volume. The goal of this note is to give…

Differential Geometry · Mathematics 2007-05-23 Gabriele Link

The statements of Main~Theorem~1.1 and Theorem~2.1 of the author's paper [\emph{Trans.\ Amer.\ Math.\ Soc.}\ {\bf 345} (1994) 577--594] should assume that $\Gamma $~is discrete and $G$~is connected. (Cors.~1.3, 5.6, and~5.8 are affected…

Representation Theory · Mathematics 2009-09-25 Dave Witte

Let $X=G/K$ be an irreducible Hermitian symmetric space of the non-compact type and let $S\in G^\mbb{C}$ be the associated compression semi-group. Let $\Gamma$ be a discrete subgroup of $G$. We give a sufficient condition for…

Complex Variables · Mathematics 2010-09-29 Christian Miebach

A graph $\Gamma$ is $G$-symmetric if it admits $G$ as a group of automorphisms acting transitively on the set of arcs of $\Gamma$, where an arc is an ordered pair of adjacent vertices. Let $\Gamma$ be a $G$-symmetric graph such that its…

Combinatorics · Mathematics 2024-03-05 Teng Fang , Sanming Zhou , Shenglin Zhou

We develop a general, functional calculus approach to approximation of $C_0$-semigroups on Banach spaces by bounded completely monotone functions of their generators. The approach comprises most of well-known approximation formulas, yields…

Functional Analysis · Mathematics 2018-07-10 A. Gomilko , S. Kosowicz , Yu. Tomilov

We show that the fundamental groupoid~\(\Pi_1(X)\) of a locally path connected semilocally simply connected space~\(X\) can be equipped with a \emph{natural} topology so that it becomes a topological groupoid; we also justify the necessity…

Algebraic Topology · Mathematics 2023-07-28 Rohit Dilip Holkar , Md Amir Hossain

Let $G$ be a group with involution * and $\sigma\colon G\to\{\pm1\}$ a group homomorphism. The map $\sharp$ that sends $\alpha=\sum\alpha_gg$ in a group ring $RG$ to $\alpha^{\sharp}=\sum\sigma(g)\alpha_gg^*$ is an involution of $RG$ called…

Group Theory · Mathematics 2011-08-24 Edgar G. Goodaire , Cesar Polcino Milies

For $2\le p<\infty$ we show the lower estimates \[ \|A^{\frac 12}x\|_p \kl c(p)\max\{\pl \|\Gamma(x,x)^{{1/2}}\|_p,\pl \|\Gamma(x^*,x^*)^{{1/2}}\|_p\} \] for the Riesz transform associated to a semigroup $(T_t)$ of completely positive maps…

Operator Algebras · Mathematics 2008-06-13 Marius Junge , Tao Mei

An orbifold is a topological space modeled on quotient spaces of a finite group actions. We can define the universal cover of an orbifold and the fundamental group as the deck transformation group. Let $G$ be a Lie group acting on a space…

Geometric Topology · Mathematics 2007-05-23 Suhyoung Choi

Conformal transformations of a Euclidean (complex) plane have some kind of completeness (sufficiency) for the solution of many mathematical and physical-mathematical problems formulated on this plane. There is no such completeness in the…

Mathematical Physics · Physics 2007-05-23 G. I. Garas'ko

In this work we use generalized deformed gauge groups for investigation of symmetry of general relativity (GR). GR is formulated in generalized reference frames, which are represented by (anholonomic in general case) affine frame fields.…

General Relativity and Quantum Cosmology · Physics 2020-06-09 S. E. Samokhvalov

For each subchain $X'$ of a chain $X$, let $T_{RE}(X, X')$ denote the semigroup under composition of all full regressive transformations, $\alpha:X\rightarrow X'$ satisfying $x\alpha\leq x$ for all $x\in X$. Necessary and sufficient…

Rings and Algebras · Mathematics 2012-10-05 Patanee Udomkavanich , Phichet Jitjankarn

A {\it graph product} $G$ on a graph $\Gamma$ is a group defined as follows: For each vertex $v$ of $\Gamma$ there is a corresponding non-trivial group $G_v$. The group $G$ is the quotient of the free product of the $G_v$ by the commutation…

Group Theory · Mathematics 2020-04-24 Michael Mihalik

Let $\Gamma$ denote a finite, connected graph with vertex set $X$. Fix $x \in X$ and let $\varepsilon \ge 3$ denote the eccentricity of $x$. For mutually distinct scalars $\{\theta^*_i\}_{i=0}^\varepsilon$ define a diagonal matrix…

Combinatorics · Mathematics 2025-03-05 Blas Fernández , Roghayeh Maleki , Štefko Miklavič , Giusy Monzillo

Let $E_G$ be a $\Gamma$--equivariant algebraic principal $G$--bundle over a normal complex affine variety $X$ equipped with an action of $\Gamma$, where $G$ and $\Gamma$ are complex linear algebraic groups. Suppose $X$ is contractible as a…

Algebraic Geometry · Mathematics 2018-06-26 Indranil Biswas , Arijit Dey , Mainak Poddar

Let $G$ be a finite group, let $\pi(G)$ be the set of prime divisors of $|G|$ and let $\Gamma(G)$ be the prime graph of $G$. This graph has vertex set $\pi(G)$, and two vertices $r$ and $s$ are adjacent if and only if $G$ contains an…

Group Theory · Mathematics 2019-02-20 Timothy C. Burness , Elisa Covato

Let $\{\phi_s\}_{s\in S}$ be a commutative semigroup of completely positive, contractive, and weak*-continuous linear maps acting on a von Neumann algebra $N$. Assume there exists a semigroup $\{\alpha_s\}_{s\in S}$ of weak*-continuous…

Operator Algebras · Mathematics 2011-07-14 Bebe Prunaru