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Motivated by three recent open questions in the study of linear dynamics, we study weighted shifts on sequence spaces. First, we provide an example of a weighted shift on a locally convex space whose topology is generated by a sequence of…

Dynamical Systems · Mathematics 2025-09-30 Michal Hevessy , Tomáš Raunig

A coordinate-free proof of the Maximum Principle is provided in the specific case of an optimal control problem with fixed time. Our treatment heavily relies on a special notion of variation of curves that consist of a concatenation of…

Differential Geometry · Mathematics 2007-05-23 B. Langerock

Given an automorphism of a smooth complex algebraic curve, there is an induced action on the moduli space of semi-stable rank 2 holomorphic bundles with fixed determinant. We give a complete description of the fixed variety in terms of…

Algebraic Geometry · Mathematics 2007-05-23 Jorgen Ellegaard Andersen , Jakob Grove

We present a simple way to discretize and precondition mixed variational formulations. Our theory connects with, and takes advantage of, the classical theory of symmetric saddle point problems and the theory of preconditioning symmetric…

Numerical Analysis · Mathematics 2018-05-18 Constantin Bacuta , Jacob Jacavage

We study the relationship between many natural conditions that one can put on a diffeological vector space: being fine or projective, having enough smooth (or smooth linear) functionals to separate points, having a diffeology determined by…

Differential Geometry · Mathematics 2019-12-25 J. Daniel Christensen , Enxin Wu

For a topological space $X$ we study continuous maps $f : X\to \mathbb R^m$ such that images of every pairwise distinct $k$ points are affinely (linearly) independent. Such maps are called affinely (linearly) $k$-regular embeddings. We…

Algebraic Topology · Mathematics 2011-06-29 R. N. Karasev

In this paper, we study some new fixed point results for self maps defined on partial metric type spaces. In particular, we give common fixed point theorems in the same setting. Some examples are given which illustrate the results.

General Topology · Mathematics 2018-09-12 Yaé Ulrich Gaba

Two classes of topological spaces are introduced on which every probability Radon measure possesses a uniformly distributed sequence or a uniformly tight uniformly distributed sequence. It is shown that these classes are stable under…

General Topology · Mathematics 2007-08-28 V. I. Bogachev , M. N. Lukintsova

We discuss the problem of finding an analogue of the concept of a topological space in supergeometry, motivated by a search for a procedure to compactify a supermanifold along odd coordinates. In particular, we examine the topologies…

General Topology · Mathematics 2007-05-23 Ugo Bruzzo , Vladimir Pestov

We introduce a saddle-point finder that can find the complex saddle points for any analytically continued action. We showcase our saddle-point finder by two examples in the EPRL spin foam model: the single vertex case and the case of…

General Relativity and Quantum Cosmology · Physics 2023-03-08 Zichang Huang , Shan Huang , Yidun Wan

In part I we considered the problem of convergence to a saddle point of a concave-convex function via gradient dynamics and an exact characterization was given to their asymptotic behaviour. In part II we consider a general class of…

Optimization and Control · Mathematics 2019-08-06 Thomas Holding , Ioannis Lestas

In this paper we make some observations concerning m-metric spaces and point out some discrepancies in the proofs found in the literature. To remedy this, we propose a new topological construction and prove that it is in fact a…

General Topology · Mathematics 2018-07-03 Samer Assaf

We study topological boundedness of order-to-topology bounded and order-to-topology continuous operators from ordered vector spaces to topological vector spaces. The uniform boundedness principle for such operators is investigated.

Functional Analysis · Mathematics 2026-03-12 Eduard Emelyanov

This paper extends sliding-mode control theory to nonlinear systems evolving on smooth manifolds. Building on differential geometric methods, we reformulate Filippov's notion of solutions, characterize well-defined vector fields on quotient…

Optimization and Control · Mathematics 2025-09-17 Fernando Castaños

The aim of this paper is to generalize some fixed point theorems in the class of convex contraction of order $m$ on a complete suprametric space. Then, we will prove that the class of convex contraction of order m is strong enough to…

General Mathematics · Mathematics 2026-05-11 Nicola Fabiano , Sedigheh Barootkoob , Hossein Lakzian

This work is the first step in a two-part investigation of real-time replica wormholes. Here we study the associated real-time gravitational path integral and construct the variational principle that will define its saddle-points. We also…

High Energy Physics - Theory · Physics 2021-06-23 Sean Colin-Ellerin , Xi Dong , Donald Marolf , Mukund Rangamani , Zhencheng Wang

In this paper, we introduce a generalized notion of monotone property and prove some results regarding existence and uniqueness of multi-tupled fixed points for nonlinear contraction mappings satisfying monotone property in ordered complete…

Functional Analysis · Mathematics 2016-10-04 Aftab Alam , Mohammad Imdad , Stojan Radenovic

We prove that a semiregular topological space $X$ is completely regular if and only if its topology is generated by a normal quasi-uniformity. This characterization implies that each regular paratopological group is completely regular. This…

General Topology · Mathematics 2021-11-01 Taras Banakh , Alex Ravsky

We investigate a tangent space at a point of a general metric space and metric space valued derivatives. The conditions under which two different subspace of a metric space have isometric tangent spaces in a common point of these subspaces…

Metric Geometry · Mathematics 2009-04-29 O. Dovgoshey

A topological space has the fixed point property if every continuous self-map of that space has at least one fixed point. We demonstrate that there are serious restraints imposed by the requirement that there be a choice of fixed points…

General Topology · Mathematics 2015-10-20 Markus Szymik