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Related papers: Convex and subharmonic functions on graphs

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We define convexity canonically in the setting of monoids. We show that many classical results from convex analysis hold for functions defined on such groups and semigroups, rather than only on vector spaces. Some examples and…

Optimization and Control · Mathematics 2015-10-16 Jonathan M. Borwein , Ohad Giladi

Graphs are naturally sparse objects that are used to study many problems involving networks, for example, distributed learning and graph signal processing. In some cases, the graph is not given, but must be learned from the problem and…

Machine Learning · Statistics 2017-08-31 Martin Sundin , Arun Venkitaraman , Magnus Jansson , Saikat Chatterjee

We will prove that a function u(x,y) defined on a domain of RpxRq that is subharmonic in one variable and harmonic in the other is (jointly) subharmonic. This solves a long-standing open problem.

Complex Variables · Mathematics 2009-06-09 Mansour Kalantar

In this paper we show how the superquadratic functions can be used as a tool for researching other types of convex functions like $\phi $-convexity, strong-convexity and uniform convexity. We show how to use inequalities satisfied by…

Functional Analysis · Mathematics 2024-08-15 Shoshana Abramovich

Graph convexity has been used as an important tool to better understand the structure of classes of graphs. Many studies are devoted to determine if a graph equipped with a convexity is a {\em convex geometry}. In this work we survey…

Discrete Mathematics · Computer Science 2024-09-05 Mitre C. Dourado , Marisa Gutierrez , Fábio Protti , Rudini Sampaio , Silvia Tondato

We consider the problem of finding a subgraph of a given graph minimizing the sum of given functions at vertices evaluated at their subgraph degrees. While the problem is NP-hard already for bipartite graphs when the functions are convex on…

Optimization and Control · Mathematics 2021-04-27 Gabriel Deza , Shmuel Onn

We analyze and characterize maximal monotonicity of linear relations (set-valued operators with linear graphs). An important tool in our study are Fitzpatrick functions. The results obtained partially extend work on linear and at most…

Functional Analysis · Mathematics 2008-05-29 Heinz H. Bauschke , Xianfu Wang , Liangjin Yao

It is established that general s-convex functions are a new class of generalized convex functions. In a similar vein, a new class of general s-convex sets is introduced, which are generalizations of s-convex sets. Additionally, certain…

Optimization and Control · Mathematics 2023-01-03 Musavvir Ali , Ehtesham Akhter

The purpose of this paper is to generalize the convexity of Mabuchi's functional to the conic setting. We first established a frame to study conic cscK metrics, and then the conic Mabuchi functional was introduced in such a way that conic…

Differential Geometry · Mathematics 2016-03-02 Long Li

For the minimal graph with strict convex level sets, we find an auxiliary function to study the Gaussian curvature of the level sets. We prove that this curvature function is a concave function with respect to the height of the minimal…

Analysis of PDEs · Mathematics 2016-01-20 Pei-He Wang

Functions with uniform level sets can represent orders, preference relations or other binary relations and thus turn out to be a tool for scalarization that can be used, e.g., in multicriteria optimization, decision theory, mathematical…

Optimization and Control · Mathematics 2016-08-11 Petra Weidner

A key idea in convex optimization theory is to use well-structured affine functions to approximate general functions, leading to impactful developments in conjugate functions and convex duality theory. This raises the question: what are the…

Optimization and Control · Mathematics 2025-04-22 Ningji Wei

We prove that, in general, given a $p$-harmonic map $F:M\to N$ and a convex function $H:N\to\mathbb{R}$, the composition $H\circ F$ is not $p$-subharmonic. By assuming some rotational symmetry on manifolds and functions, we reduce the…

Analysis of PDEs · Mathematics 2011-06-07 Giona Veronelli

There has been a great deal of attention recently to graphs whose vertex set is a group, defined using the group structure. (The commuting graph, where two elements are joined if they commute, is the oldest and most famous example.) The…

Combinatorics · Mathematics 2026-02-03 Peter J. Cameron

In this paper, we introduce a new subclass of close-to-convex harmonic functions. We present a sufficient coefficient condition for a function to be a member of this class. Furthermore, we establish a distortion theorem. These results lay…

Complex Variables · Mathematics 2025-02-10 Serkan Çakmak , Sibel Yalçin

Graph is an abstract representation commonly used to model networked systems and structure. In problems across various fields, including computer vision and pattern recognition, and neuroscience, graphs are often brought into comparison (a…

Optimization and Control · Mathematics 2022-03-04 Quoc Van Tran , Hyo-Sung Ahn

In this paper some concepts of convex analysis on hyperbolic space are studied. We first study properties of the intrinsic distance, for instance, we present the spectral decomposition of its Hessian. Next, we study the concept of convex…

Optimization and Control · Mathematics 2022-07-13 Orizon Pereira Ferreira , Sándor Zoltán Németh , Jinzhen Zhu

First, we give the definition for quasi-nearly subharmonic functions, now for general, not necessarily nonnegative functions, unlike previously. We point out that our function class incudes, among others, quasisubharmonic functions, nearly…

Analysis of PDEs · Mathematics 2008-10-08 Juhani Riihentaus

We consider sets and maps defined over an o-minimal structure over the reals, such as real semi-algebraic or subanalytic sets. A {\em monotone map} is a multi-dimensional generalization of a usual univariate monotone function, while the…

Logic · Mathematics 2013-08-19 Saugata Basu , Andrei Gabrielov , Nicolai Vorobjov

Functions with uniform sublevel sets can represent orders, preference relations or other binary relations and thus turn out to be a tool for scalarization that can be used in multicriteria optimization, decision theory, mathematical…

Optimization and Control · Mathematics 2017-12-06 Petra Weidner