Results 71 to 80 of about 175,704,569 (186)

On matrix transformations and Hausdorff measure of noncompactness of Euler difference sequence spaces of fractional order

, 2021
In the present paper, some results on matrix mappings and Hausdorff measure of noncompactness of certain generalized Euler difference sequence spaces of fractional order are discussed.
Kadak, Ugur, Baliarsingh, P.
core  

Nonlinear Integrodifferential Equations of Mixed Type in Banach Spaces

International Journal of Mathematics and Mathematical Sciences, 2007
We prove two existence theorems for the integrodifferential equation of mixed type: x'(t)=f(t,x(t),∫0tk1(t,s)g(s,x(s))ds,∫0ak2(t,s)h(s,x(s))ds), x(0)=x0, where in the first part of this paper f, g, h, x are functions with values in a Banach space E and ...
Aneta Sikorska-Nowak, Grzegorz Nowak
doaj   +1 more source

Surface subgroups for cocompact lattices of isometries of H2n$\mathbb {H}^{2n}$

Journal of Topology, Volume 19, Issue 3, September 2026.
Abstract We prove the existence of surface subgroups within any cocompact lattice Γ$\Gamma$ in SO(2n,1)$\mathrm{SO}(2n,1)$ for n⩾2$n\geqslant 2$. This result addresses the cases missing from the work of Hamenstädt in 2015, who constructed surface subgroups in cocompact lattices for all other rank‐1 simple Lie groups of noncompact type.
Jeremy Kahn, Zhenghao Rao
wiley   +1 more source

Higher representation stability for ordered configuration spaces

Journal of Topology, Volume 19, Issue 3, September 2026.
Abstract Using factorization homology with coefficients in twisted commutative algebras (TCAs), we prove two flavors of higher representation stability for the cohomology of (generalized) configuration spaces of a scheme/topological space X$X$. First, we provide an iterative procedure to study higher representation stability using actions coming from ...
Quoc P. Ho
wiley   +1 more source

Existence of solutions of infinite systems of nonlinear Volterra integral equations on a Fréchet space

پژوهش‌های ریاضی, 2021
In this paper, we introduce a Fréchet space  and define a measure of noncompactness on it.  For credit and the application to our theorems, in the application section of this paper, we present a theorem which shows the existence of solution of infinite ...
Hogat Allah Amiri kayvanloo, Mahnaz Khanehgir, Reza Allahyari   +2 more
doaj  

Simple homotopy theory for Fukaya categories

Journal of Topology, Volume 19, Issue 3, September 2026.
Abstract We develop a categorical framework for simple homotopy theory in Fukaya categories, based on the fundamental group of the ambient symplectic manifold. When the first Chern class vanishes, we show that any isomorphism in the Fukaya category of a Weinstein manifold has trivial Whitehead torsion.
Yonghwan Kim
wiley   +1 more source

n-tuplet fixed points of multivalued mappings via measure of noncompactness

, 2017
In this paper, some results on the existence of n-tuplet fixed points formulti-valued contraction mappings are proved via measure of noncompactness.
KARAKAYA, Vatan, BOUZARA, NOUR EL HOUDA, SEKMAN, Derya   +2 more
core   +1 more source

Solvability of second order linear differential equations in the sequence space n(ϕ) $n(\phi)$

Advances in Difference Equations, 2018
We apply the concept of measure of noncompactness to study the existence of solution of second order differential equations with initial conditions in the sequence space n(ϕ) $n(\phi)$.
Abdullah Alotaibi, M. Mursaleen, Badriah A. S. Alamri   +2 more
doaj   +1 more source

Finiteness of the Hölder–Brascamp–Lieb constant revisited

Bulletin of the London Mathematical Society, Volume 58, Issue 8, August 2026.
Abstract Abstract Hölder–Brascamp–Lieb inequalities have become a ubiquitous tool in Fourier analysis in recent years, due in large part to a theorem of Bennett et al. characterizing finiteness of the Hölder–Brascamp–Lieb constant. Here we provide a new characterization of a substantially different nature involving directed graphs of subspaces.
Philip T. Gressman
wiley   +1 more source

Measures of noncompactness and their applications

, 2021
The measures of noncompactness are very useful tools in the theory of operatorequations in Banach spaces. In particular, the fixed point theorems derived fromthem have many important results. In this study, we state a general information onmeasures of noncompactness and fixed point theory. In addition, applications fromvarious topics are presented.
openaire   +1 more source