English
Related papers

Related papers: Riemann-Roch Theory for Graph Orientations

200 papers

We give practical algorithms for computing the divisor class group and the gonality of a curve over a finite field, achieving several orders of magnitude speedup over existing methods for sufficiently large genus or residue field. The…

Number Theory · Mathematics 2026-02-20 Maarten Derickx , Kenji Terao

Circle graphs are intersection graphs of chords of a circle. In this paper, we present a new algorithm for the circle graph isomorphism problem running in time $O((n+m)\alpha(n+m))$ where $n$ is the number of vertices, $m$ is the number of…

Data Structures and Algorithms · Computer Science 2019-08-27 Vít Kalisz , Pavel Klavík , Peter Zeman

In the final paper of the Graph Minors series N. Robertson and P. Seymour proved that graphs are well-quasi-ordered under the immersion ordering. A direct implication of this theorem is that each class of graphs that is closed under taking…

Data Structures and Algorithms · Computer Science 2015-03-20 Archontia C. Giannopoulou , Iosif Salem , Dimitris Zoros

We develop a theory of confluence of graphs. We describe an algorithm for proving that a given system of reduction rules for abstract graphs and graphs in surfaces is locally confluent. We apply this algorithm to show that each simple Lie…

Quantum Algebra · Mathematics 2014-10-01 Adam S. Sikora , Bruce W. Westbury

In this paper we extend a recent result of Collin-Rosenberg ({\it a solution to the minimal surface equation in the Euclidean disc has radial limits almost everywhere}) to a large class of differential operators in Divergence form.…

Differential Geometry · Mathematics 2009-04-19 Jose M. Espinar , Harold Rosenberg

The minimum feedback arc set problem asks to delete a minimum number of arcs (directed edges) from a digraph (directed graph) to make it free of any directed cycles. In this work we approach this fundamental cycle-constrained optimization…

Disordered Systems and Neural Networks · Physics 2017-09-13 Yi-Zhi Xu , Hai-Jun Zhou

In this paper we consider the problem of distributed nonlinear optimisation of a separable convex cost function over a graph subject to cone constraints. We show how to generalise, using convex analysis, monotone operator theory and…

Distributed, Parallel, and Cluster Computing · Computer Science 2024-05-16 Richard Heusdens , Guoqiang Zhang

The minimum semi-degree of a digraph D is the minimum of its minimum outdegree and its minimum indegree. We show that every sufficiently large digraph D with minimum semi-degree at least n/2 +k-1 is k-linked. The bound on the minimum…

Combinatorics · Mathematics 2007-05-23 Daniela Kühn , Deryk Osthus

We consider the question of orienting the edges in a graph $G$ such that every vertex has bounded out-degree. For graphs of arboricity $\alpha$, there is an orientation in which every vertex has out-degree at most $\alpha$ and, moreover,…

Data Structures and Algorithms · Computer Science 2025-01-07 Slobodan Mitrović , Ronitt Rubinfeld , Mihir Singhal

We make progress on three long standing conjectures from the 1960s about path and cycle decompositions of graphs. Gallai conjectured that any connected graph on $n$ vertices can be decomposed into at most $\left\lceil…

Combinatorics · Mathematics 2022-02-09 António Girão , Bertille Granet , Daniela Kühn , Deryk Osthus

The main result of the paper is motivated by the following two, apparently unrelated graph optimization problems: (A) as an extension of Edmonds' disjoint branchings theorem, characterize digraphs comprising $k$ disjoint branchings $B_i$…

Combinatorics · Mathematics 2017-09-05 Kristóf Bérczi , András Frank

Acyclic digraphs are the underlying representation of Bayesian networks, a widely used class of probabilistic graphical models. Learning the underlying graph from data is a way of gaining insights about the structural properties of a…

Machine Learning · Statistics 2022-05-06 Jack Kuipers , Giusi Moffa

We develop a general embedding method based on the Friedman-Pippenger tree embedding technique (1987) and its algorithmic version, essentially due to Aggarwal et al. (1996), enhanced with a roll-back idea allowing to sequentially retrace…

Combinatorics · Mathematics 2021-03-22 Nemanja Draganić , Michael Krivelevich , Rajko Nenadov

How does one generalize differential geometric constructs such as curvature of a manifold to the discrete world of graphs and other combinatorial structures? This problem carries significant importance for analyzing models of discrete…

Combinatorics · Mathematics 2023-06-27 J. F. Du Plessis , Xerxes D. Arsiwalla

We show a deterministic constant-time local algorithm for constructing an approximately maximum flow and minimum fractional cut in multisource-multitarget networks with bounded degrees and bounded edge capacities. Locality means that the…

Data Structures and Algorithms · Computer Science 2023-11-03 Endre Csóka , András Pongrácz

In the present paper we extend the Riemann-Roch formalism to structure algebras of moment graphs. We introduce and study the Chern character and pushforwards for twisted fibrations of moment graphs. We prove an analogue of the Riemann-Roch…

Algebraic Geometry · Mathematics 2020-03-06 Martina Lanini , Kirill Zainoulline

We derive and analyse a new iterative algorithm for detecting network core--periphery structure. Using techniques in nonlinear Perron-Frobenius theory, we prove global convergence to the unique solution of a relaxed version of a natural…

Social and Information Networks · Computer Science 2019-02-12 Francesco Tudisco , Desmond J. Higham

A minimum cycle basis of a weighted undirected graph $G$ is a basis of the cycle space of $G$ such that the total weight of the cycles in this basis is minimized. If $G$ is a planar graph with non-negative edge weights, such a basis can be…

Discrete Mathematics · Computer Science 2009-12-08 Christian Wulff-Nilsen

Let $G$ be a graph of order $n$. The maximum and minimum degree of $G$ are denoted by $\Delta$ and $\delta$ respectively. The \emph{path partition number} $\mu (G)$ of a graph $G$ is the minimum number of paths needed to partition the…

Combinatorics · Mathematics 2022-12-27 M. Kouider , M. Zamime

We break the symmetry in classical spectral bi-partitioning in order to incentivise the alignment of directed cut edges. We use this to generate acyclic bi-partitions and furthermore topological orders of directed acyclic graphs with superb…

Data Structures and Algorithms · Computer Science 2025-08-25 Dimosthenis Pasadakis , Raphael S. Steiner , Pál András Papp , Toni Böhnlein , Albert-Jan N. Yzelman