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The analysis of observable phenomena (for instance, in biology or physics) allows the detection of dynamical behaviors and, conversely, starting from a desired behavior allows the design of objects exhibiting that behavior in engineering.…

Discrete Mathematics · Computer Science 2026-04-10 Antonio E. Porreca , Marius Rolland

In this short note, we give a new sufficient condition for a linear map from a product of copies of a field to endomorphisms of a finite dimensional vector space over the same field to be an algebra homomorphism. We expect that this result…

Rings and Algebras · Mathematics 2015-07-31 Rajesh S. Kulkarni , Yusuf Mustopa , Ian Shipman

We link the study of positive quantum maps, block positive operators, and entanglement witnesses with problems related to multivariate polynomials. For instance, we show how indecomposable block positive operators relate to biquadratic…

Mathematical Physics · Physics 2009-11-28 Lukasz Skowronek , Karol Zyczkowski

This paper is concerned with the factorization and equivalence problems of multivariate polynomial matrices. We present some new criteria for the existence of matrix factorizations for a class of multivariate polynomial matrices, and obtain…

Symbolic Computation · Computer Science 2020-10-15 Dong Lu , Dingkang Wang , Fanghui Xiao

We study the extent to which standard machine learning algorithms rely on exchangeability and independence of data by introducing a monotone adversarial corruption model. In this model, an adversary, upon looking at a "clean" i.i.d.…

Machine Learning · Computer Science 2026-01-06 Kasper Green Larsen , Chirag Pabbaraju , Abhishek Shetty

This paper proves that the characteristic polynomial is a complete unitary invariant for pairs of projection matrices. Some special cases involving three or more projections are also considered.

Representation Theory · Mathematics 2023-10-13 Kate Howell , Rongwei Yang

We study countable embedding-universal and homomorphism-universal structures and unify results related to both of these notions. We show that many universal and ultrahomogeneous structures allow a concise description (called here a finite…

Combinatorics · Mathematics 2010-09-06 Jan Hubicka

This thesis investigates the central role of homomorphism problems (structure-preserving maps) in two complementary domains: database querying over finite, graph-shaped data, and constraint solving over (potentially infinite) structures.…

Logic in Computer Science · Computer Science 2025-10-10 Rémi Morvan

Simplicial complexes prove effective in modeling data with multiway dependencies, such as data defined along the edges of networks or within other higher-order structures. Their spectrum can be decomposed into three interpretable subspaces…

Machine Learning · Computer Science 2023-09-15 Alexander Möllers , Alexander Immer , Vincent Fortuin , Elvin Isufi

A good feature representation is a determinant factor to achieve high performance for many machine learning algorithms in terms of classification. This is especially true for techniques that do not build complex internal representations of…

Neural and Evolutionary Computing · Computer Science 2019-08-22 Noëlie Cherrier , Jean-Philippe Poli , Maxime Defurne , Franck Sabatié

When a linear order has an order preserving surjection onto each of its suborders we say that it is strongly surjective. We prove that the set of countable strongly surjective linear orders is complete for the class of sets which are the…

Logic · Mathematics 2020-06-30 Riccardo Camerlo , Raphaël Carroy , Alberto Marcone

One-class classification (OCC) algorithms aim to build classification models when the negative class is either absent, poorly sampled or not well defined. This unique situation constrains the learning of efficient classifiers by defining…

Machine Learning · Computer Science 2018-02-05 Shehroz S. Khan , Michael G. Madden

Prior work of Gavryushkin, Khoussainov, Jain and Stephan investigated what algebraic structures can be realised in worlds given by a positive (= recursively enumerable) equivalence relation which partitions the natural numbers into…

Logic in Computer Science · Computer Science 2021-06-21 David Belanger , Ziyuan Gao , Sanjay Jain , Wei Li , Frank Stephan

Recent years have seen a surprising connection between the physics of scattering amplitudes and a class of mathematical objects--the positive Grassmannian, positive loop Grassmannians, tree and loop Amplituhedra--which have been loosely…

High Energy Physics - Theory · Physics 2017-12-06 Nima Arkani-Hamed , Yuntao Bai , Thomas Lam

Architectural imperatives due to the slowing of Moore's Law, the broad acceptance of relaxed semantics and the O(n!) worst case verification complexity of generating sequential histories motivate a new approach to concurrent correctness.…

Distributed, Parallel, and Cluster Computing · Computer Science 2019-07-17 Victor Cook , Christina Peterson , Zachary Painter , Damian Dechev

In this tutorial, we will survey known results on the complexity of conjunctive query evaluation in different settings, ranging from Boolean queries over counting to more complex models like enumeration and direct access. A particular focus…

Databases · Computer Science 2025-06-24 Stefan Mengel

A Qualitative Constraint Network (QCN) is a constraint graph for representing problems under qualitative temporal and spatial relations, among others. More formally, a QCN includes a set of entities, and a list of qualitative constraints…

Artificial Intelligence · Computer Science 2021-09-27 Malek Mouhoub , Hamad Al Marri , Eisa Alanazi

Features in machine learning problems are often time-varying and may be related to outputs in an algebraic or dynamical manner. The dynamic nature of these machine learning problems renders current higher order accelerated gradient descent…

Optimization and Control · Mathematics 2019-05-29 Joseph E. Gaudio , Travis E. Gibson , Anuradha M. Annaswamy , Michael A. Bolender

Abstract notions of convexity over the vertices of a graph, and corresponding notions of halfspaces, have recently gained attention from the machine learning community. In this work we study monophonic halfspaces, a notion of graph…

Machine Learning · Computer Science 2025-07-01 Marco Bressan , Victor Chepoi , Emmanuel Esposito , Maximilian Thiessen

Contrastive learning produces coherent semantic feature embeddings by encouraging positive samples to cluster closely while separating negative samples. However, existing contrastive learning methods lack principled guarantees on coverage…

Machine Learning · Computer Science 2026-03-30 Yahya Alkhatib , Wee Peng Tay