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3 | The Co-annihilating-ideal Graphs of Commutative Rings Akbari, Saeeid; Alilou, Abbas; Amjadi, Jafar; Sheikholeslami, Seyed Mahmoud
Let $R$ be a commutative ring with identity. The
co-annihilating-ideal graph of $R$, denoted by $\mathcal{A}_R$,
is
a graph whose vertex set is the set of all non-zero proper ideals
of $R$ and two distinct vertices $I$ and $J$ are adjacent
whenever ${\operatorname {Ann}}(I)\cap {\operatorname {Ann}}(J)=\{0\}$. In this paper we
initiate the study of the co-annihilating ideal graph of a
commutative ring and we investigate its properties.
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12 | Co-maximal Graphs of Subgroups of Groups Akbari, Saieed; Miraftab, Babak; Nikandish, Reza
Let $H$ be a group. The co-maximal graph of subgroups
of $H$, denoted by $\Gamma(H)$, is a
graph whose vertices are non-trivial and proper subgroups of
$H$ and two distinct vertices $L$
and $K$ are adjacent in $\Gamma(H)$ if and only if $H=LK$. In
this paper, we study the connectivity, diameter, clique number
and vertex
chromatic number of $\Gamma(H)$. For instance, we show that
if $\Gamma(H)$ has no isolated vertex, then $\Gamma(H)$
is connected with diameter at most $3$. Also, we characterize
all finite groups whose co-maximal graphs are connected.
Among other results, we show that if $H$ is a finitely generated
solvable group and $\Gamma(H)$ is connected and moreover the
degree of a maximal subgroup is finite, then $H$ is finite.
Furthermore, we show that the degree of each vertex in the
co-maximal graph of a general linear group over an algebraically
closed field is zero or infinite.
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26 | Self $2$-distance Graphs Azimi, Ali; Farrokhi Derakhshandeh Ghouchan, Mohammad
All finite simple self $2$-distance graphs with no square, diamond,
or triangles with a common vertex as subgraph are determined.
Utilizing these results, it is shown that there is no cubic self
$2$-distance graph.
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43 | On the Dual König Property of the Order-interval Hypergraph of Two Classes of N-free Posets Bouchemakh, Isma; Fatma, Kaci
Let $P$ be a finite N-free poset. We consider the hypergraph
$\mathcal{H}(P)$ whose vertices are the elements of $P$ and whose
edges are the maximal intervals of $P$. We study the dual
König property of $\mathcal{H}(P)$ in two subclasses of N-free class.
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54 | Tubular Free by Cyclic Groups Act Freely on CAT(0) Cube Complexes Button, Jack
We identify when a tubular group (the fundamental group of a
finite
graph of groups with $\mathbb{Z}^2$ vertex and $\mathbb{Z}$ edge groups) is free
by
cyclic and show, using Wise's equitable sets criterion, that
every
tubular free by
cyclic group acts freely on a CAT(0) cube complex.
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63 | Power Series Rings Over Prüfer $v$-multiplication Domains, II Chang, Gyu Whan
Let $D$ be an integral domain, $X^1(D)$ be the set of height-one
prime ideals of $D$,
$\{X_{\beta}\}$ and $\{X_{\alpha}\}$ be
two disjoint nonempty sets of indeterminates over $D$,
$D[\{X_{\beta}\}]$ be the polynomial ring over $D$, and
$D[\{X_{\beta}\}][\![\{X_{\alpha}\}]\!]_1$ be the first type
power series ring over $D[\{X_{\beta}\}]$.
Assume that $D$ is a Prüfer $v$-multiplication domain (P$v$MD)
in which each proper integral $t$-ideal has only finitely many
minimal prime ideals
(e.g., $t$-SFT P$v$MDs, valuation domains, rings of Krull type).
Among other things, we show that if
$X^1(D) = \emptyset$ or $D_P$ is a DVR for all $P \in X^1(D)$,
then
${D[\{X_{\beta}\}][\![\{X_{\alpha}\}]\!]_1}_{D - \{0\}}$ is a
Krull domain.
We also prove that if $D$ is a $t$-SFT P$v$MD, then the complete
integral closure of $D$ is a Krull domain and
ht$(M[\{X_{\beta}\}][\![\{X_{\alpha}\}]\!]_1)$ = $1$ for every
height-one maximal $t$-ideal $M$ of $D$.
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77 | Nilpotent Group C*-algebras as Compact Quantum Metric Spaces Christ, Michael; Rieffel, Marc A.
Let $\mathbb{L}$ be a length function on a group $G$, and let $M_\mathbb{L}$
denote the
operator of pointwise multiplication by $\mathbb{L}$ on $\lt(G)$.
Following Connes,
$M_\mathbb{L}$ can be used as a ``Dirac'' operator for the reduced
group C*-algebra $C_r^*(G)$. It defines a
Lipschitz seminorm on $C_r^*(G)$, which defines a metric on the
state space of
$C_r^*(G)$. We show that
for any length function satisfying a strong form of polynomial
growth on a discrete group,
the topology from this metric
coincides with the
weak-$*$ topology (a key property for the
definition of a ``compact quantum metric
space''). In particular, this holds for all word-length functions
on finitely generated nilpotent-by-finite groups.
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95 | Cubic Functional Equations on Restricted Domains of Lebesgue Measure Zero Choi, Chang-Kwon; Chung, Jaeyoung; Ju, Yumin; Rassias, John
Let $X$ be a real normed space, $Y$ a Bancch space and $f:X \to
Y$.
We prove the Ulam-Hyers stability theorem
for the cubic functional equation
\begin{align*}
f(2x+y)+f(2x-y)-2f(x+y)-2f(x-y)-12f(x)=0
\end{align*}
in restricted domains. As an application we consider a measure
zero stability problem
of the inequality
\begin{align*}
\|f(2x+y)+f(2x-y)-2f(x+y)-2f(x-y)-12f(x)\|\le \epsilon
\end{align*}
for all $(x, y)$ in $\Gamma\subset\mathbb R^2$ of Lebesgue measure
0.
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104 | An Extension of Nikishin's Factorization Theorem Diestel, Geoff
A Nikishin-Maurey characterization is given for bounded subsets
of weak-type Lebesgue spaces. New factorizations for linear and
multilinear operators are shown to follow.
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111 | Abstract Plancherel (Trace) Formulas over Homogeneous Spaces of Compact Groups Ghaani Farashahi, Arash
This paper introduces a unified operator theory approach to the
abstract Plancherel (trace) formulas over
homogeneous spaces of compact groups. Let $G$ be a compact group
and $H$ be a closed subgroup of $G$.
Let $G/H$ be the left coset space of $H$ in $G$ and $\mu$ be
the normalized $G$-invariant measure on $G/H$ associated to the
Weil's formula.
Then, we present a generalized abstract notion of Plancherel
(trace) formula for the Hilbert space $L^2(G/H,\mu)$.
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122 | A Homological Property and Arens Regularity of Locally Compact Quantum Groups Ghanei, Mohammad Reza; Nasr-Isfahani, Rasoul; Nemati, Mehdi
We characterize two important notions of amenability and compactness
of
a locally compact quantum group ${\mathbb G}$ in terms of certain
homological
properties. For this, we show that ${\mathbb G}$ is character
amenable if and only if it is both amenable and co-amenable.
We finally apply our results to
Arens regularity problems of the quantum group algebra
$L^1({\mathbb G})$; in particular, we improve an interesting result
by Hu, Neufang and Ruan.
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131 | Some Estimates for Generalized Commutators of Rough Fractional Maximal and Integral Operators on Generalized Weighted Morrey Spaces Gürbüz, Ferit
In this paper, we establish $BMO$ estimates for generalized commutators
of
rough fractional maximal and integral operators on generalized
weighted
Morrey spaces, respectively.
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146 | The Dirichlet Problem for the Slab with Entire Data and a Difference Equation for Harmonic Functions Khavinson, Dmitry; Lundberg, Erik; Render, Hermann
It is shown that the Dirichlet problem for the slab $(a,b) \times
\mathbb{R}^{d}$ with entire boundary data has an entire solution. The proof
is based
on a generalized Schwarz reflection principle. Moreover, it is
shown that
for a given entire harmonic function $g$
the inhomogeneous difference equation $h
( t+1,y) -h (t,y) =g ( t,y)$
has an entire harmonic solution $h$.
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154 | On Chromatic Functors and Stable Partitions of Graphs Liu, Ye
The chromatic functor of a simple graph is a functorization of
the chromatic polynomial. M. Yoshinaga showed
that two finite graphs have isomorphic chromatic functors if
and only if they have the same chromatic polynomial. The key
ingredient in the proof is the use of stable partitions of graphs.
The latter is shown to be closely related to chromatic functors.
In this note, we further investigate some interesting properties
of chromatic functors associated to simple graphs using stable
partitions. Our first result is the determination of the group
of natural automorphisms of the chromatic functor, which is in
general a larger group than the automorphism group of the graph.
The second result is that the composition of the chromatic functor
associated to a finite graph restricted to the category $\mathrm{FI}$
of finite sets and injections with the free functor into the
category of complex vector spaces yields a consistent sequence
of representations of symmetric groups which is representation
stable in the sense of Church-Farb.
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165 | Cokernels of Homomorphisms from Burnside Rings to Inverse Limits Morimoto, Masaharu
Let $G$ be a finite group and
let $A(G)$ denote the Burnside ring of $G$.
Then an inverse limit $L(G)$ of the groups $A(H)$ for
proper subgroups $H$ of $G$ and a homomorphism
${\operatorname{res}}$ from $A(G)$ to $L(G)$ are obtained in a natural
way.
Let $Q(G)$ denote the cokernel of ${\operatorname{res}}$.
For a prime $p$,
let $N(p)$ be the minimal
normal subgroup of $G$ such that the order of $G/N(p)$ is
a power of $p$, possibly $1$.
In this paper we prove that $Q(G)$ is isomorphic to
the cartesian product of the groups $Q(G/N(p))$, where $p$
ranges over the primes dividing the order of $G$.
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173 | On Ulam Stability of a Functional Equation in Banach Modules Oubbi, Lahbib
Let $X$ and $Y$ be Banach spaces and $f : X \to Y$ an odd mapping.
For any rational number $r \ne 2$, C. Baak, D. H.
Boo, and Th. M. Rassias have proved the Hyers-Ulam stability
of the following functional equation:
\begin{align*}
r f
\left(\frac{\sum_{j=1}^d x_j}{r}
\right)
& + \sum_{\substack{i(j) \in \{0,1\}
\\ \sum_{j=1}^d i(j)=\ell}} r f
\left(
\frac{\sum_{j=1}^d (-1)^{i(j)}x_j}{r}
\right)
= (C^\ell_{d-1} - C^{\ell -1}_{d-1} + 1) \sum_{j=1}^d
f(x_j)
\end{align*}
where $d$ and $\ell$ are positive integers so that $1 \lt \ell
\lt \frac{d}{2}$, and $C^p_q := \frac{q!}{(q-p)!p!}$,
$p, q \in \mathbb{N}$ with $p \le q$.
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184 | On a Conjecture of Livingston Pathak, Siddhi
In an attempt to resolve a folklore conjecture of Erdös regarding
the non-vanishing at $s=1$ of the $L$-series
attached to a periodic arithmetical function with period $q$
and values in $\{ -1, 1\} $, Livingston conjectured the $\bar{\mathbb{Q}}$
- linear independence of logarithms of certain algebraic numbers.
In this paper, we disprove Livingston's conjecture for composite
$q \geq 4$, highlighting that a new approach is required to settle
Erdös's conjecture. We also prove that the conjecture is
true for prime $q \geq 3$, and indicate that more ingredients
will be needed to settle Erdös's conjecture for prime $q$.
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196 | Corrigendum to "Generalized Cesàro Matrices" Rhaly, H. C. Jr.
This note corrects an error in Theorem 1 of
"Generalized Cesàro matrices"
Canad. Math. Bull. 27 (1984), no. 4, 417-422.
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197 | Degree Kirchhoff Index of Bicyclic Graphs Tang, Zikai; Deng, Hanyuan
Let $G$ be a connected graph with vertex set $V(G)$. The degree
Kirchhoff index of $G$ is defined as $S'(G) =\sum_{\{u,v\}\subseteq
V(G)}d(u)d(v)R(u,v)$, where $d(u)$ is the degree of vertex $u$,
and
$R(u, v)$ denotes the resistance distance between vertices $u$
and
$v$. In this paper, we characterize the graphs having maximum
and
minimum degree Kirchhoff index among all $n$-vertex bicyclic
graphs
with exactly two cycles.
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206 | The Metric Dimension of Circulant Graphs Vetrik, Tomáš
A subset $W$ of the vertex set of a graph $G$ is called a resolving
set of $G$ if for every pair of distinct vertices $u, v$ of $G$,
there is $w \in W$ such that the~distance of $w$ and $u$ is different
from the distance of $w$ and $v$. The~cardinality of a~smallest
resolving set is called the metric dimension of $G$, denoted
by $dim(G)$. The circulant graph $C_n (1, 2, \dots , t)$ consists
of the vertices $v_0, v_1, \dots , v_{n-1}$ and the~edges $v_i
v_{i+j}$, where $0 \le i \le n-1$, $1 \le j \le t$ $(2 \le t
\le \lfloor \frac{n}{2} \rfloor)$, the indices are taken modulo
$n$. Grigorious et al. [On the metric dimension of circulant
and Harary graphs, Applied Mathematics and Computation 248 (2014),
47--54] proved that $dim(C_n (1,2, \dots , t))
\ge t+1$ for $t \lt \lfloor \frac{n}{2} \rfloor$, $n \ge 3$, and they
presented a~conjecture saying that $dim(C_n (1,2, \dots , t))
= t+p-1$ for $n=2tk+t+p$, where $3 \le p \le t+1$. We disprove
both statements. We show that if $t \ge 4$ is even, there exists
an infinite set of values of $n$ such that $dim(C_n (1,2, \dots
, t)) = t$. We also prove that $dim(C_n (1,2, \dots , t)) \le
t + \frac{p}{2}$ for $n=2tk+t+p$, where $t$ and $p$ are even,
$t \ge 4$, $2 \le p \le t$ and $k \ge 1$.
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217 | Condition $C'_{\wedge}$ of Operator Spaces Wang, Yuanyi
In this paper, we study condition $C'_{\wedge}$ which is a
projective tensor product analogue of condition $C'$. We show
that
the finite-dimensional OLLP operator spaces have condition
$C'_{\wedge}$ and $M_{n}$ $(n\gt 2)$ does not have that property.
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225 | Faltings' Finiteness Dimension of Local Cohomology Modules Over Local Cohen-Macaulay Rings Bahmanpour, Kamal; Naghipour, Reza
Let $(R, \frak m)$ denote a local Cohen-Macaulay ring and $I$
a non-nilpotent ideal of $R$. The purpose of this article is
to investigate Faltings' finiteness
dimension $f_I(R)$ and equidimensionalness of certain homomorphic
image of $R$. As a consequence
we deduce that $f_I(R)=\operatorname{max}\{1, \operatorname{ht} I\}$
and if $\operatorname{mAss}_R(R/I)$
is contained in $\operatorname{Ass}_R(R)$, then the ring $R/ I+\cup_{n\geq
1}(0:_RI^n)$ is equidimensional of dimension $\dim R-1$.
Moreover, we will obtain a lower bound for injective dimension
of the local cohomology module $H^{\operatorname{ht} I}_I(R)$, in the case
$(R, \frak m)$ is a complete equidimensional local ring.
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235 | Topology of Certain Quotient Spaces of Stiefel Manifolds Basu, Samik; Subhash, B
We compute the cohomology of the right generalised projective
Stiefel manifolds. Following this, we discuss some easy applications
of the computations to the ranks of complementary bundles, and
bounds on the span and immersibility.
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246 | On Radicals of Green's Relations in Ordered Semigroups Bhuniya, Anjan Kumar; Hansda, Kalyan
In this paper, we give a new definition of radicals of Green's
relations in an ordered semigroup and characterize left regular
(right regular), intra regular ordered semigroups by radicals
of Green's relations. Also we characterize the ordered semigroups
which are unions and complete semilattices of t-simple ordered
semigroups.
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253 | On a Yamabe Type Problem in Finsler Geometry Chen, Bin; Zhao, Lili
In this paper, a new notion of scalar curvature for a Finsler
metric $F$ is introduced, and two conformal invariants $Y(M,F)$
and $C(M,F)$ are defined. We prove that there exists a Finsler
metric with constant scalar curvature in the conformal class
of $F$ if the Cartan torsion of $F$ is sufficiently small and
$Y(M,F)C(M,F)\lt Y(\mathbb{S}^n)$ where $Y(\mathbb{S}^n)$ is the
Yamabe constant of the standard sphere.
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269 | Characterizations and Representations of Core and Dual Core Inverses Chen, Jianlong; Zhu, Huihui; Patricio, Pedro; Zhang, Yulin
In this
paper,
double commutativity and the reverse order law for the core inverse
are considered. Then, new characterizations of the Moore-Penrose
inverse of a regular element are given by one-sided invertibilities
in a ring. Furthermore, the characterizations and representations
of
the core and dual core inverses of a regular element are considered.
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283 | Twisted Alexander Invariants Detect Trivial Links Friedl, Stefan; Vidussi, Stefano
It follows from earlier work of Silver--Williams and the authors
that twisted Alexander polynomials detect the unknot and the
Hopf link.
We now show that twisted Alexander polynomials also detect the
trefoil and the figure-8 knot,
that twisted Alexander polynomials detect whether a link is split
and that twisted Alexander modules detect trivial links. We use
this result to provide algorithms for detecting whether a link
is the unlink, whether it is split and whether it is totally
split.
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300 | Luzin-type Holomorphic Approximation on Closed Subsets of Open Riemann Surfaces Gauthier, Paul M; Sharifi, Fatemeh
It is known that if $E$ is a closed subset of an open Riemann
surface $R$ and $f$ is a holomorphic function on a neighbourhood
of $E,$ then it is ``usually" not possible to approximate $f$
uniformly by functions holomorphic on all of $R.$ We show, however,
that for every open Riemann surface $R$ and every closed subset
$E\subset R,$ there is closed subset $F\subset E,$ which approximates
$E$ extremely well, such that every function holomorphic on $F$
can be approximated much better than uniformly by functions holomorphic
on $R$.
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309 | A Congruence Modulo Four for Real Schubert Calculus with Isotropic Flags Hein, Nickolas; Sottile, Frank; Zelenko, Igor
We previously obtained a congruence modulo four for the number
of real solutions to many Schubert problems on
a square Grassmannian given by osculating flags.
Here, we consider Schubert problems given by more general isotropic
flags, and prove this
congruence modulo four for the largest class of Schubert problems
that could be expected to exhibit this
congruence.
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319 | The Weakly Nilpotent Graph of a Commutative Ring Khojasteh, Sohiela; Nikmehr, Mohammad Javad
Let $R$ be a commutative ring with non-zero identity. In this
paper, we introduced the weakly nilpotent graph of a commutative
ring. The weakly nilpotent graph of $R$ is denoted by $\Gamma_w(R)$
is a graph with the vertex set $R^{*}$ and two vertices $x$ and
$y$ are adjacent if and only if $xy\in N(R)^{*}$, where $R^{*}=R\setminus\{0\}$
and $N(R)^{*}$ is the set of all non-zero nilpotent elements
of $R$. In this article, we determine the diameter of weakly
nilpotent graph of an Artinian ring. We prove that if $\Gamma_w(R)$
is a forest, then $\Gamma_w(R)$ is a union of a star and some
isolated vertices. We study the clique number, the chromatic
number and the independence number of $\Gamma_w(R)$. Among other
results, we show that for an Artinian ring $R$, $\Gamma_w(R)$
is not a disjoint union of cycles or a unicyclic graph. For Artinan
ring, we determine $\operatorname{diam}(\overline{\Gamma_w(R)})$. Finally, we
characterize all commutative rings $R$ for which $\overline{\Gamma_w(R)}$
is a cycle, where $\overline{\Gamma_w(R)}$ is the complement
of the weakly nilpotent graph of $R$.
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329 | Nonvanishing of Central Values of $L$-functions of Newforms in $S_2 (\Gamma_0 (dp^2))$ Twisted by Quadratic Characters Le Fourn, Samuel
We prove that for $d \in \{ 2,3,5,7,13 \}$ and $K$ a quadratic
(or rational) field of discriminant $D$ and Dirichlet character
$\chi$, if a prime $p$ is large enough compared to $D$, there
is a newform $f \in S_2(\Gamma_0(dp^2))$ with sign $(+1)$ with
respect to the Atkin-Lehner involution $w_{p^2}$ such that $L(f
\otimes \chi,1) \neq 0$. This result is obtained through an estimate
of a weighted sum of twists of $L$-functions which generalises
a result of Ellenberg. It relies on the approximate functional
equation for the $L$-functions $L(f \otimes \chi, \cdot)$ and
a Petersson trace formula restricted to Atkin-Lehner eigenspaces.
An application of this nonvanishing theorem will be given in
terms of existence of rank zero quotients of some twisted jacobians,
which generalises a result of Darmon and Merel.
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350 | Isometry on Linear $n$-G-quasi Normed Spaces Ma, Yumei
This paper generalizes the Aleksandrov problem: the Mazur-Ulam
theorem on $n$-G-quasi normed spaces. It proves that a one-$n$-distance
preserving mapping is an $n$-isometry if and only if it has the
zero-$n$-G-quasi preserving property, and two kinds of $n$-isometries
on $n$-G-quasi normed space are equivalent; we generalize the
Benz theorem to n-normed spaces with no restrictions on the dimension
of spaces.
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364 | On the Roughness of Quasinilpotency Property of One–parameter Semigroups Preda, Ciprian
Let $\mathbf{S}:=\{S(t)\}_{t\geq0}$ be a C$_0$-semigroup of quasinilpotent
operators
(i.e. $\sigma(S(t))=\{0\}$ for each $t\gt 0$).
In the dynamical systems theory the above quasinilpotency property
is equivalent
to a very strong concept of stability for the solutions of autonomous
systems.
This concept is frequently called superstability and weakens
the classical finite time extinction property
(roughly speaking, disappearing solutions).
We show that under some assumptions, the quasinilpotency, or
equivalently, the superstability property
of a C$_0$-semigroup is preserved under the perturbations of
its infinitesimal generator.
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372 | Coaxer Lattices Rao, M. Sambasiva
The notion of coaxers is introduced in a pseudo-complemented
distributive lattice. Boolean algebras are characterized in terms
of coaxer ideals and congruences. The concept of coaxer lattices
is introduced in pseudo-complemented distributive lattices and
characterized in terms of coaxer ideals and maximal ideals. Finally,
the coaxer lattices are also characterized in topological terms.
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381 ![]() | The Bifurcation Diagram of Cubic Polynomial Vector Fields on $\mathbb{C}\mathbb{P}^1$ Rousseau, C.
In this paper we give the bifurcation diagram
of the family of cubic vector fields $\dot z=z^3+ \epsilon_1z+\epsilon_0$
for $z\in \mathbb{C}\mathbb{P}^1$, depending on the values of
$\epsilon_1,\epsilon_0\in\mathbb{C}$.
The bifurcation diagram is in $\mathbb{R}^4$, but its conic structure
allows describing it for parameter values in $\mathbb{S}^3$. There are
two open simply connected regions of structurally stable vector
fields separated by surfaces corresponding to bifurcations of
homoclinic connections between two separatrices of the pole at
infinity. These branch from the codimension 2 curve of double
singular points. We also explain the bifurcation of homoclinic
connection in terms of the description of Douady and Sentenac
of polynomial vector fields.
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402 | Invariant Means on a Class of von Neumann Algebras Related to Ultraspherical Hypergroups II Shravan Kumar, N.
Let $K$ be an ultraspherical hypergroup associated to a locally
compact group $G$ and a spherical projector $\pi$ and let $VN(K)$
denote the dual of the Fourier algebra $A(K)$ corresponding to
$K.$ In this note, we show that the set of invariant means on
$VN(K)$ is singleton if and only if $K$ is discrete. Here $K$
need not be second countable. We also study invariant means on
the dual of the Fourier algebra $A_0(K),$ the closure of $A(K)$
in the $cb$-multiplier norm. Finally, we consider generalized
translations and generalized invariant means.
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411 | On Gibbs Measures and Spectra of Ruelle Transfer Operators Stoyanov, Luchezar
We prove a comprehensive version of the Ruelle-Perron-Frobenius
Theorem
with explicit estimates of the spectral radius of the Ruelle
transfer operator and various other
quantities related to spectral properties of this operator. The
novelty here is that the Hölder
constant of the function generating the operator appears only
polynomially, not exponentially as
in previous known estimates.
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422 | New Super-quadratic Conditions for Asymptotically Periodic Schrödinger Equations Tang, Xianhua
This paper is dedicated to studying the
semilinear Schrödinger equation
$$
\left\{
\begin{array}{ll}
-\triangle u+V(x)u=f(x, u), \ \ \ \ x\in {\mathbf{R}}^{N},
\\
u\in H^{1}({\mathbf{R}}^{N}),
\end{array}
\right.
$$
where $f$ is a superlinear, subcritical nonlinearity. It focuses
on the case where
$V(x)=V_0(x)+V_1(x)$, $V_0\in C(\mathbf{R}^N)$, $V_0(x)$ is 1-periodic
in each of $x_1, x_2, \ldots, x_N$ and
$\sup[\sigma(-\triangle +V_0)\cap (-\infty, 0)]\lt 0\lt \inf[\sigma(-\triangle
+V_0)\cap (0, \infty)]$,
$V_1\in C(\mathbf{R}^N)$ and $\lim_{|x|\to\infty}V_1(x)=0$. A new super-quadratic
condition is obtained,
which is weaker than some well known results.
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436 | Globally Asymptotic Stability of a Delayed Integro-Differential Equation with Nonlocal Diffusion Weng, Peixuan; Liu, Li
We study a population model with nonlocal diffusion, which
is a delayed integro-differential equation with double nonlinearity
and two integrable kernels. By comparison method and analytical
technique, we obtain globally asymptotic stability of the zero
solution and the positive equilibrium. The results obtained
reveal that the globally asymptotic stability only depends on
the property of nonlinearity. As application, an example for
a population model with age structure is discussed at the end
of the article.
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449 | Character Density in Central Subalgebras of Compact Quantum Groups Alaghmandan, Mahmood; Crann, Jason
We investigate quantum group generalizations
of various density results from Fourier analysis on compact groups.
In particular, we establish the density of characters in the
space of fixed points of the conjugation action on $L^2(\mathbb{G})$, and
use this result to show the weak* density and norm density of
characters in $ZL^\infty(\mathbb{G})$ and $ZC(\mathbb{G})$, respectively. As a corollary,
we partially answer an open question of Woronowicz.
At the level of $L^1(\mathbb{G})$, we show that the center
$\mathcal{Z}(L^1(\mathbb{G}))$
is precisely the closed linear span of the quantum characters
for a large class of compact quantum groups, including arbitrary
compact Kac algebras. In the latter setting, we show, in addition,
that $\mathcal{Z}(L^1(\mathbb{G}))$ is a completely complemented
$\mathcal{Z}(L^1(\mathbb{G}))$-submodule
of $L^1(\mathbb{G})$.
|
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462 | Functions Universal for All Translation Operators in Several Complex Variables Bayart, Frédéric; Gauthier, Paul M
We prove the existence of
a (in fact many)
holomorphic function $f$ in $\mathbb{C}^d$ such that, for any $a\neq
0$, its translations $f(\cdot+na)$ are dense in $H(\mathbb{C}^d)$.
|
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470 | Maurer-Cartan Elements in the Lie Models of Finite Simplicial Complexes Buijs, Urtzi; Félix, Yves; Murillo, Aniceto; Tanré, Daniel
In a previous work, we have associated a complete differential
graded Lie algebra
to any finite simplicial complex in a functorial way.
Similarly, we have also a realization functor from the category
of complete differential graded Lie algebras
to the category of simplicial sets.
We have already interpreted the homology of a Lie algebra
in terms of homotopy groups of its realization.
In this paper, we begin a dictionary between models
and simplicial complexes by establishing a correspondence
between the Deligne groupoid of the model and the connected components
of the finite simplicial complex.
|
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478 | Springer's Weyl Group Representation via Localization Carrell, Jim; Kaveh, Kiumars
Let $G$ denote a reductive algebraic group over
$\mathbb{C}$
and $x$ a nilpotent element of its Lie algebra $\mathfrak{g}$. The Springer
variety $\mathcal{B}_x$
is the closed subvariety of the flag variety $\mathcal{B}$ of $G$ parameterizing
the
Borel subalgebras of $\mathfrak{g}$ containing $x$. It has the remarkable
property that
the Weyl group $W$ of $G$ admits a representation on the cohomology
of $\mathcal{B}_x$
even though $W$ rarely acts on $\mathcal{B}_x$ itself. Well-known constructions
of this action
due to Springer et al use technical machinery from algebraic
geometry.
The purpose of this note is to describe an elementary approach
that gives this action
when $x$ is what we call parabolic-surjective. The idea is to
use localization to construct an action of $W$ on
the equivariant cohomology algebra $H_S^*(\mathcal{B}_x)$, where $S$ is a certain algebraic
subtorus of $G$.
This action descends to $H^*(\mathcal{B}_x)$ via the forgetful map and
gives the desired representation. The parabolic-surjective case
includes all nilpotents of type $A$ and,
more generally, all nilpotents for which it is known that $W$
acts on
$H_S^*(\mathcal{B}_x)$ for some torus $S$.
Our result is deduced from a general theorem describing
when a group action on the cohomology of the fixed point set of a
torus action
on a space lifts to the full cohomology algebra of the space.
|
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484 | A Note on Lawton's Theorem Dobrowolski, Edward
We prove Lawton's conjecture about the upper bound on the measure
of the set on the unit circle on which a complex polynomial with
a bounded number of coefficients takes small values. Namely,
we prove that Lawton's bound holds for polynomials that are not
necessarily monic. We also provide an analogous bound for polynomials
in several variables. Finally, we investigate the dependence
of the bound on the multiplicity of zeros for polynomials in
one variable.
|
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490 | A Riemann-Hurwitz Theorem for the Algebraic Euler Characteristic Fiori, Andrew
We prove an analogue of the Riemann-Hurwitz theorem for computing
Euler characteristics of pullbacks of coherent sheaves through
finite maps of smooth projective varieties in arbitrary dimensions,
subject only to the condition that the irreducible components
of the branch and ramification locus have simple normal crossings.
|
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510 | Convex-normal (Pairs of) Polytopes Haase, Christian; Hofmann, Jan
In 2012 Gubeladze (Adv. Math. 2012)
introduced the notion of $k$-convex-normal polytopes to show
that
integral polytopes all of whose edges are longer than $4d(d+1)$
have
the integer decomposition property.
In the first part of this paper we show that for lattice polytopes
there is no difference between $k$- and $(k+1)$-convex-normality
(for
$k\geq 3 $) and improve the bound to $2d(d+1)$. In the second
part we
extend the definition to pairs of polytopes. Given two rational
polytopes $P$ and $Q$, where the normal fan of $P$ is a refinement
of
the normal fan of $Q$.
If every edge $e_P$ of $P$ is at least $d$ times as long as the
corresponding face (edge or vertex) $e_Q$ of $Q$, then $(P+Q)\cap
\mathbb{Z}^d
= (P\cap \mathbb{Z}^d ) + (Q \cap \mathbb{Z}^d)$.
|
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522 | On the Singular Sheaves in the Fine Simpson Moduli Spaces of $1$-dimensional Sheaves Iena, Oleksandr; Leytem, Alain
In the Simpson moduli space $M$ of semi-stable sheaves with
Hilbert polynomial $dm-1$ on a projective plane we study the
closed subvariety $M'$ of sheaves that are not locally free on
their support. We show that for $d\ge 4$ it is a singular subvariety
of codimension $2$ in $M$. The blow up of $M$ along $M'$ is interpreted
as a (partial) modification of $M\setminus M'$ by line bundles
(on support).
|
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536 | The Gradient of a Solution of the Poisson Equation in the Unit Ball and Related Operators Kalaj, David; Vujadinović, Djordjije
In this paper we determine the $L^1\to L^1$ and $L^{\infty}\to
L^\infty$ norms of an integral operator $\mathcal{N}$ related
to the gradient of the solution of Poisson equation in the unit
ball with vanishing boundary data in sense of distributions.
|
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546 | On Polarized K3 Surfaces of Genus 33 Karzhemanov, Ilya
We prove that the moduli space of smooth primitively polarized
$\mathrm{K3}$ surfaces of genus $33$ is unirational.
|
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561 | Nuij Type Pencils of Hyperbolic Polynomials Kurdyka, Krzysztof; Paunescu, Laurentiu
Nuij's theorem states that if a polynomial $p\in \mathbb{R}[z]$ is hyperbolic
(i.e. has only real roots) then $p+sp'$ is also hyperbolic for
any
$s\in \mathbb{R}$. We study other perturbations of hyperbolic polynomials
of the form $p_a(z,s): =p(z) +\sum_{k=1}^d a_ks^kp^{(k)}(z)$.
We give a full characterization of those $a= (a_1, \dots,
a_d) \in \mathbb{R}^d$ for which $p_a(z,s)$ is a pencil of hyperbolic
polynomials.
We give also a full characterization of those $a= (a_1, \dots,
a_d) \in \mathbb{R}^d$ for which the associated families $p_a(z,s)$
admit universal determinantal representations. In fact we show
that all these sequences come from special symmetric Toeplitz
matrices.
|
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571 | Weak Factorizations of the Hardy space $H^1(\mathbb{R}^n)$ in terms of Multilinear Riesz Transforms Li, Ji; Wick, Brett D.
This paper provides a constructive proof of the weak factorization
of the classical Hardy space $H^1(\mathbb{R}^n)$ in terms of
multilinear Riesz transforms. As a direct application, we obtain
a new proof of the characterization of ${\rm BMO}(\mathbb{R}^n)$
(the dual of $H^1(\mathbb{R}^n)$) via commutators of the multilinear
Riesz transforms.
|
|||||
586 | Endpoint Regularity of Multisublinear Fractional Maximal Functions Liu, Feng; Wu, Huoxiong
In this paper we investigate
the endpoint regularity properties of the multisublinear
fractional maximal operators, which include the multisublinear
Hardy-Littlewood maximal operator. We obtain some new bounds
for the derivative of the one-dimensional multisublinear
fractional maximal operators acting on vector-valued function
$\vec{f}=(f_1,\dots,f_m)$ with all $f_j$ being $BV$-functions.
|
|||||
604 | Stackings and the $W$-cycles Conjecture Louder, Larsen; Wilton, Henry
We prove Wise's $W$-cycles conjecture: Consider a compact graph
$\Gamma'$ immersing into another graph $\Gamma$. For any immersed
cycle $\Lambda:S^1\to \Gamma$, we consider the map $\Lambda'$
from
the circular components $\mathbb{S}$ of the pullback to $\Gamma'$.
Unless
$\Lambda'$ is reducible, the degree of the covering map $\mathbb{S}\to
S^1$ is bounded above by minus the Euler characteristic of
$\Gamma'$. As a corollary, any finitely generated subgroup
of a
one-relator group has finitely generated Schur multiplier.
|
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613 | On the Dimension of the Locus of Determinantal Hypersurfaces Reichstein, Zinovy; Vistoli, Angelo
The characteristic polynomial $P_A(x_0, \dots,
x_r)$
of an $r$-tuple $A := (A_1, \dots, A_r)$ of $n \times n$-matrices
is
defined as
\[ P_A(x_0, \dots, x_r) := \det(x_0 I + x_1 A_1 + \dots + x_r
A_r) \, . \]
We show that if $r \geqslant 3$
and $A := (A_1, \dots, A_r)$ is an $r$-tuple of $n \times n$-matrices in general position,
then up to conjugacy, there are only finitely many $r$-tuples
$A' := (A_1', \dots, A_r')$ such that $p_A = p_{A'}$. Equivalently,
the locus of determinantal hypersurfaces of degree $n$ in $\mathbf{P}^r$
is irreducible of dimension $(r-1)n^2 + 1$.
|
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631 | Traceless Maps as the Singular Minimizers in the Multi-dimensional Calculus of Variations Shahrokhi-Dehkordi, M. S.
Let $\Omega \subset \mathbb{R}^n$ be a bounded Lipschitz domain and
consider
the energy functional
\begin{equation*}
{\mathcal F}[u, \Omega] := \int_{\Omega} {\rm F}(\nabla {\bf u}(\bf x))\, d{\bf x},
\end{equation*}
over the space of $W^{1,2}(\Omega, \mathbb{R}^m)$ where the integrand
${\rm F}: \mathbb M_{m\times n}\to \mathbb{R}$ is a smooth uniformly
convex function
with bounded second derivatives. In this paper we address the
question of
regularity for solutions of the corresponding system of
Euler-Lagrange equations.
In particular we introduce a class of singular maps referred
to as traceless and
examine them as a new counterexample to the regularity of minimizers
of the energy
functional $\mathcal F[\cdot,\Omega]$ using a method based on
null Lagrangians.
|
|||||
641 | Mixed $f$-divergence for Multiple Pairs of Measures Werner, Elisabeth; Ye, Deping
In this paper, the concept of the classical $f$-divergence for
a pair of measures is extended to the mixed $f$-divergence for
multiple pairs of measures. The mixed $f$-divergence provides
a way to measure the difference between multiple pairs of (probability)
measures. Properties for the mixed $f$-divergence are established,
such as permutation invariance and symmetry in distributions.
An
Alexandrov-Fenchel type inequality and an isoperimetric inequality
for the
mixed $f$-divergence are proved.
|
|||||
655 | Characterizations of Besov-Type and Triebel-Lizorkin-Type Spaces via Averages on Balls Zhuo, Ciqiang; Sickel, Winfried; Yang, Dachun; Yuan, Wen
Let $\ell\in\mathbb N$ and $\alpha\in (0,2\ell)$. In this article,
the authors establish
equivalent characterizations
of Besov-type spaces, Triebel-Lizorkin-type
spaces and Besov-Morrey spaces via the sequence
$\{f-B_{\ell,2^{-k}}f\}_{k}$ consisting of the difference between
$f$ and
the ball average $B_{\ell,2^{-k}}f$. These results give a way
to introduce Besov-type spaces,
Triebel-Lizorkin-type spaces and Besov-Morrey spaces with any
smoothness order
on metric measure spaces. As special cases, the authors obtain
a new characterization of Morrey-Sobolev spaces
and $Q_\alpha$ spaces with $\alpha\in(0,1)$, which are of independent
interest.
|
|||||
673 | Character Amenability of the Intersection of Lipschitz Algebras Abtahi, Fatemeh; Azizi, Mohsen; Rejali, Ali
Let $(X,d)$ be a metric space and $J\subseteq [0,\infty)$ be
nonempty. We study the structure of the arbitrary intersections
of
Lipschitz algebras, and define a special Banach subalgebra of
$\bigcap_{\gamma\in J}\operatorname{Lip}_\gamma X$, denoted by
$\operatorname{ILip}_J X$. Mainly,
we investigate $C$-character amenability of $\operatorname{ILip}_J X$, in
particular Lipschitz algebras. We address a gap in the proof
of a
recent result in this field. Then we remove this gap, and obtain
a
necessary and sufficient condition for $C$-character amenability
of $\operatorname{ILip}_J X$, specially Lipschitz algebras, under an additional
assumption.
|
|||||
690 | $\mathcal{Q}_p$ Spaces and Dirichlet Type Spaces Bao, Guanlong; Göğüş, Nıhat Gökhan; Pouliasis, Stamatis
In this paper, we show that the Möbius invariant
function space $\mathcal {Q}_p$ can be generated by variant
Dirichlet type spaces
$\mathcal{D}_{\mu, p}$ induced by finite positive Borel measures
$\mu$ on the open unit disk. A criterion for the equality between
the space $\mathcal{D}_{\mu, p}$ and the usual Dirichlet type
space $\mathcal {D}_p$ is given. We obtain a sufficient condition
to construct different $\mathcal{D}_{\mu, p}$ spaces
and we provide examples.
We establish decomposition theorems for $\mathcal{D}_{\mu,
p}$ spaces, and prove that the non-Hilbert space $\mathcal
{Q}_p$ is equal to the intersection of Hilbert spaces $\mathcal{D}_{\mu,
p}$. As an application of the relation between $\mathcal {Q}_p$
and $\mathcal{D}_{\mu, p}$ spaces, we also obtain that there
exist different $\mathcal{D}_{\mu, p}$ spaces; this is a trick
to prove the existence without constructing examples.
|
|||||
705 | Envelope Approach to Degenerate Complex Monge-Ampère Equations on Compact Kähler Manifolds Benelkourchi, Slimane
We shall use the classical Perron envelope method to show a general
existence theorem to degenerate complex
Monge-Ampère type equations on compact Kähler manifolds.
|
|||||
712 | Disjoint Hypercyclicity and Weighted Translations on Discrete Groups Chen, Chung-Chuan
Let $1\leq p\lt \infty$, and let $G$ be a discrete group. We give
a sufficient and necessary condition
for weighted translation operators on the Lebesgue space $\ell^p(G)$
to be densely disjoint hypercyclic.
The characterization for the dual of a weighted translation to
be densely disjoint hypercyclic is also obtained.
|
|||||
721 | On Identities with Composition of Generalized Derivations Eroǧlu, Münevver Pınar; Argaç, Nurcan
Let $R$ be a prime ring with extended
centroid $C$, $Q$ maximal right ring of quotients of $R$, $RC$
central closure of $R$ such that $dim_{C}(RC)
\gt 4$, $f(X_{1},\dots,X_{n})$
a multilinear polynomial over $C$ which is not central-valued
on $R$ and $f(R)$ the set of all evaluations of the multilinear
polynomial $f\big(X_{1},\dots,X_{n}\big)$ in $R$. Suppose that
$G$ is a nonzero generalized derivation of $R$ such that $G^2\big(u\big)u
\in C$ for all $u\in f(R)$ then one of the following conditions
holds:
|
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736 ![]() | Levi's Problem for Pseudoconvex Homogeneous Manifolds Gilligan, Bruce
Suppose $G$ is a connected complex Lie group and $H$ is a closed
complex subgroup.
Then there exists a closed complex subgroup $J$ of $G$ containing
$H$ such that
the fibration $\pi:G/H \to G/J$ is the holomorphic reduction
of $G/H$, i.e., $G/J$ is holomorphically
separable and ${\mathcal O}(G/H) \cong \pi^*{\mathcal O}(G/J)$.
In this paper we prove that if $G/H$ is pseudoconvex, i.e.,
if
$G/H$ admits a continuous plurisubharmonic exhaustion function,
then $G/J$ is Stein and $J/H$ has no non--constant holomorphic
functions.
|
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747 | Injectivity of Generalized Wronski Maps Huang, Yanhe; Sottile, Frank; Zelenko, Igor
We study linear projections on Plücker space whose restriction
to the Grassmannian is a non-trivial branched
cover.
When an automorphism of the Grassmannian preserves the fibers,
we show that the Grassmannian is necessarily
of $m$-dimensional linear subspaces in a symplectic vector
space of dimension $2m$, and the linear map is
the Lagrangian involution.
The Wronski map for a self-adjoint linear differential operator
and pole placement map for
symmetric linear systems are natural examples.
|
|||||
762 | Maximal Weight Composition Factors for Weyl Modules Jantzen, Jens Carsten
Fix an irreducible (finite) root system $R$ and a choice
of positive roots. For any algebraically closed field $k$ consider the almost simple, simply connected algebraic group $G_k$ over $k$ with root system $k$. One associates to any dominant weight $\lambda$ for $R$ two $G_k$--modules with highest weight $\lambda$, the
Weyl module $V (\lambda)_k$ and its simple quotient $L (\lambda)_k$.
Let $\lambda$ and $\mu$ be dominant weights with $\mu \lt \lambda$ such
that
$\mu$ is maximal with this property. Garibaldi, Guralnick, and
Nakano
have asked under which condition there exists $k$ such that $L
(\mu)_k$
is a composition factor of $V (\lambda)_k$, and they exhibit an
example
in type $E_8$ where this is not the case. The purpose of this
paper
is to to show that their example is the only one. It contains
two proofs
for this fact, one that uses a classification of the possible
pairs $(\lambda, \mu)$,
and another one that relies only on the classification
of root systems.
|
|||||
774 | On the Structure of the Schild Group in Relativity Theory Jensen, Gerd; Pommerenke, Christian
Alfred Schild has established conditions
that Lorentz transformations map world-vectors $(ct,x,y,z)$ with
integer coordinates onto vectors of the same kind. These transformations
are called integral Lorentz transformations.
|
|||||
791 | Reduction to Dimension Two of Local Spectrum for $AH$ Algebra with Ideal Property Jiang, Chunlan
A $C^{*}$-algebra $A$ has the ideal property if any ideal
$I$ of $A$ is generated as a closed two sided ideal by the projections
inside the ideal. Suppose that the limit $C^{*}$-algebra $A$
of inductive limit of direct sums of matrix algebras over spaces
with uniformly bounded dimension has ideal property. In this
paper we will prove that $A$ can be written as an inductive limit
of certain very special subhomogeneous algebras, namely, direct
sum of dimension drop interval algebras and matrix algebras over
2-dimensional spaces with torsion $H^{2}$ groups.
|
|||||
807 | The Shifted Classical Circulant and Skew Circulant Splitting Iterative Methods for Toeplitz Matrices Liu, Zhongyun; Qin, Xiaorong; Wu, Nianci; Zhang, Yulin
It is known that every Toeplitz matrix $T$ enjoys a circulant
and skew circulant splitting (denoted by CSCS)
i.e., $T=C-S$ with $C$ a circulant matrix and $S$ a skew circulant
matrix. Based on the variant of such a splitting (also referred
to as CSCS), we first develop classical CSCS iterative methods
and then introduce shifted CSCS iterative methods for solving
hermitian positive definite Toeplitz systems in this paper. The
convergence of each method is analyzed. Numerical experiments
show that the classical CSCS iterative methods work slightly
better than the Gauss-Seidel (GS) iterative methods if the CSCS
is convergent, and that there is always a constant $\alpha$ such
that the shifted CSCS iteration converges much faster than the
Gauss-Seidel iteration, no matter whether the CSCS itself is
convergent or not.
|
|||||
816 | Characterizations of Operator Birkhoff--James Orthogonality Moslehian, Mohammad Sal; Zamani, Ali
In this paper, we obtain some characterizations of the (strong)
Birkhoff--James orthogonality for elements of Hilbert $C^*$-modules
and certain elements of $\mathbb{B}(\mathscr{H})$.
Moreover, we obtain a kind of Pythagorean relation for bounded
linear operators.
In addition, for $T\in \mathbb{B}(\mathscr{H})$ we prove that if the
norm attaining
set $\mathbb{M}_T$ is a unit sphere of some finite dimensional
subspace $\mathscr{H}_0$ of $\mathscr{H}$ and $\|T\|_{{{\mathscr{H}}_0}^\perp}
\lt \|T\|$, then for every $S\in\mathbb{B}(\mathscr{H})$, $T$ is the strong
Birkhoff--James orthogonal to $S$ if and only if there exists
a unit vector $\xi\in {\mathscr{H}}_0$ such that $\|T\|\xi =
|T|\xi$ and $S^*T\xi = 0$.
Finally, we introduce a new type of approximate orthogonality
and investigate this notion in the setting of inner product $C^*$-modules.
|
|||||
830 | Generalized Torsion Elements and Bi-orderability of 3-manifold Groups Motegi, Kimihiko; Teragaito, Masakazu
It is known that a bi-orderable group has no generalized torsion
element,
but the converse does not hold in general.
We conjecture that the converse holds for the fundamental groups
of $3$-manifolds,
and verify the conjecture for non-hyperbolic, geometric $3$-manifolds.
We also confirm the conjecture for some infinite families of
closed hyperbolic $3$-manifolds.
In the course of the proof,
we prove that each standard generator of the Fibonacci group
$F(2, m)$ ($m \gt 2$) is a generalized torsion element.
|
|||||
845 | Continuity of Convolution and SIN Groups Pachl, Jan; Steprāns, Juris
Let the measure algebra of a topological group $G$ be equipped
with
the topology of uniform convergence on bounded right uniformly
equicontinuous sets of functions.
Convolution is separately continuous on the measure algebra,
and it is jointly continuous if and only if $G$ has the SIN property.
On the larger space $\mathsf{LUC}(G)^\ast$ which includes the measure
algebra,
convolution is also jointly continuous if and only if the group
has the SIN property,
but not separately continuous for many non-SIN groups.
|
|||||
855 | The Kottman Constant for $\alpha$-Hölder Maps Suárez de la Fuente, Jesús
We investigate the role of the Kottman constant
of a Banach space $X$ in the extension of $\alpha$-Hölder continuous
maps for every $\alpha\in (0,1]$.
|
|||||
861 | Characterizations of Outer Generalized Inverses Wang, Long; Castro-Gonzalez, Nieves; Chen, Jianlong
Let $R$
be a ring and $b, c\in R$.
In this paper, we give some characterizations of the $(b,c)$-inverse,
in terms of the direct sum decomposition, the annihilator and
the invertible elements.
Moreover, elements with equal $(b,c)$-idempotents related to
their $(b, c)$-inverses are characterized, and the reverse order
rule for the $(b,c)$-inverse is considered.
|
|||||
872 | Rational Function Operators from Poisson Integrals Xu, Xu; Zhu, Laiyi
In this paper, we construct two classes of rational function
operators by using the Poisson integrals of the function on the
whole real
axis. The convergence rates of the uniform and mean approximation
of such rational function operators on the whole real axis are
studied.
|
|||||
879 | Triangulated Equivalences Involving Gorenstein Projective Modules Zheng, Yuefei; Huang, Zhaoyong
For any ring $R$, we show that, in the bounded derived category
$D^{b}(\operatorname{Mod} R)$ of left $R$-modules,
the subcategory of complexes with finite Gorenstein projective
(resp. injective) dimension modulo the subcategory
of complexes with finite projective (resp. injective) dimension
is equivalent to
the stable category $\underline{\mathbf{GP}}(\operatorname{Mod} R)$ (resp.
$\overline{\mathbf{GI}}(\operatorname{Mod} R)$)
of Gorenstein projective (resp. injective) modules. As a consequence,
we get that if $R$ is a left and right noetherian ring admitting
a dualizing complex,
then $\underline{\mathbf{GP}}(\operatorname{Mod} R)$ and
$\overline{\mathbf{GI}}(\operatorname{Mod}
R)$ are equivalent.
|
|