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We introduce floating bodies for convex, not necessarily bounded subsets of $\mathbb{R}^n$. This allows us to define floating functions for convex and log concave functions and log concave measures. We establish the asymptotic behavior of…

Functional Analysis · Mathematics 2018-08-07 Ben Li , Carsten Schuett , Elisabeth M. Werner

Area-preserving nontwist maps are used to describe a broad range of physical systems. In those systems, the violation of the twist condition leads to nontwist characteristic phenomena, such as reconnection-collision sequences and shearless…

Chaotic Dynamics · Physics 2023-03-01 G. C. Grime , M. Roberto , R. L. Viana , Y. Elskens , I. L. Caldas

We give a survey of the theory of affine spheres, emphasizing the convex cases and relationsships to Monge-Ampere equations and geometric structures on manifolds.

Differential Geometry · Mathematics 2008-09-09 John Loftin

We propose to extend ``invertibility'' to ``regularity'' for categories in general abstract algebraic manner. Higher regularity conditions and ``semicommutative'' diagrams are introduced. Distinction between commutative and…

Mathematical Physics · Physics 2007-05-23 Steven Duplij , Wladyslaw Marcinek

Extending classical results on polytopal approximation of convex bodies, we derive asymptotic formulas for the weighted approximation of smooth convex functions by piecewise affine convex functions as the number of their facets tends to…

Optimization and Control · Mathematics 2025-10-01 Fernanda M. Baêta

The aim of this paper is to present a survey of some recent results obtained in the study of spaces with asymmetric norm. The presentation follows the ideas from the theory of normed spaces (topology, continuous linear operators, continuous…

Functional Analysis · Mathematics 2016-08-14 S. Cobzaş

The fundamental theorem of affine geometry says that a self-bijection $f$ of a finite-dimensional affine space over a possibly skew field takes left affine subspaces to left affine subspaces of the same dimension, then $f$ of the expected…

Rings and Algebras · Mathematics 2017-02-27 A. G. Gorinov

Two classical results characterizing regularity of a convergence space in terms of continuous extensions of maps on one hand, and in terms of continuity of limits for the continuous convergence on the other, are extended to…

General Topology · Mathematics 2014-10-31 Eva Colebunders , Frédéric Mynard , Will Trott

As an application of Brouwer's fixed-point theorem we prove that a continuously differentiable convex function with gradient of constant norm is an affine mapping. It is a first-order characterization of affine mappings among continuously…

Classical Analysis and ODEs · Mathematics 2025-11-10 Csaba Vincze

Traditionally, most complex intelligence architectures are extremely non-convex, which could not be well performed by convex optimization. However, this paper decomposes complex structures into three types of nodes: operators, algorithms…

Machine Learning · Computer Science 2018-01-16 Han Xiao

Polyconvexity is an important concept in the analysis of energies related to elasticity. A function $f \colon \R^{d\times d} \to \R$ is called polyconvex if it can be written as a convex function in the minors of the argument. We show that…

Analysis of PDEs · Mathematics 2025-11-25 David Wiedemann , Malte A. Peter

Positive bi-linear maps between matrix algebras play important roles to detect tri-partite entanglement by the duality between bi-linear maps and tri-tensor products. We exhibit indecomposable positive bi-linear maps between $2\times 2$…

Functional Analysis · Mathematics 2017-09-21 Seung-Hyeok Kye

We introduce the notion of porous invariants for multipath (or branching/nondeterministic) affine loops over the integers; these invariants are not necessarily convex, and can in fact contain infinitely many 'holes'. Nevertheless, we show…

Logic in Computer Science · Computer Science 2021-06-02 Engel Lefaucheux , Joël Ouaknine , David Purser , James Worrell

There are several notions of a smooth map from a convex set to a cartesian space. Some of these notions coincide, but not all of them do. We construct a real-valued function on a convex subset of the plane that does not extend to a smooth…

Differential Geometry · Mathematics 2023-02-15 Yael Karshon , Jordan Watts

We analyze invariant measures of two coupled piecewise linear and everywhere expanding maps on the synchronization manifold. We observe that though the individual maps have simple and smooth functions as their stationary densities, they…

Chaotic Dynamics · Physics 2017-08-11 Deepak Jalla , Kiran M. Kolwankar

For a simple model of shallow and wide neural networks, we show that the epigraph of its input-output map as a function of the network parameters approximates epigraph of a. convex function in a precise sense. This leads to a plausible…

Machine Learning · Statistics 2025-09-05 Vivek Borkar , Parthe Pandit

We present a novel and effective binary representation for convex shapes. We show the equivalence between the shape convexity and some properties of the associated indicator function. The proposed method has two advantages. Firstly, the…

Numerical Analysis · Mathematics 2020-02-25 Shousheng Luo , Xue-Cheng Tai , Yang Wang

We introduce a class of maps from an affine flat into a Riemannian manifold that solve an elliptic system defined by the natural second order elliptic operator of the affine structure and the nonlinear Riemann geometry of the target. These…

Differential Geometry · Mathematics 2010-12-17 Jürgen Jost , Fatma Muazzez Şimşir

Let F be a continuous injective map from an open subset of R^n to R^n. Assume that, for infinitely many k>1, F induces a bijection between the rational points of denominator k in the domain and those in the image (the denominator of…

Number Theory · Mathematics 2011-05-10 Giovanni Panti

The class of stochastic maps, that is, linear, trace-preserving, positive maps between the self-adjoint trace class operators of complex separable Hilbert spaces plays an important role in the representation of reversible dynamics and…

Mathematical Physics · Physics 2013-03-27 Paul Busch