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A complex hyperplane arrangement $\mathcal{A}$ is said to be decomposable if there are no elements in the degree 3 part of its holonomy Lie algebra besides those coming from the rank 2 flats. When this purely combinatorial condition is…

Group Theory · Mathematics 2025-09-30 Alexander I. Suciu

Apolarity is an important tool in commutative algebra and algebraic geometry which studies a form, $f$, by the action of polynomial differential operators on $f$. The quotient of all polynomial differential operators by those which…

Commutative Algebra · Mathematics 2020-02-13 Michael DiPasquale , Zachary Flores , Chris Peterson

Assume that $X= {x_1,...,x_g}$ is a finite alphabet and $K$ is a field. We study monomial algebras $A= K <X> /(W)$, where $W$ is an antichain of Lyndon words in $X$ of arbitrary cardinality. We find a Poincar\'{e}-Birkhoff-Witt type basis…

Rings and Algebras · Mathematics 2016-09-30 Tatiana Gateva-Ivanova , Gunnar Fløystad

CLP(H) is an instantiation of the general constraint logic programming scheme with the constraint domain of hedges. Hedges are finite sequences of unranked terms, built over variadic function symbols and three kinds of variables: for terms,…

Logic in Computer Science · Computer Science 2016-08-08 Besik Dundua , Mário Florido , Temur Kutsia , Mircea Marin

We consider the computation of the volume of the union of high-dimensional geometric objects. While showing that this problem is #P-hard already for very simple bodies (i.e., axis-parallel boxes), we give a fast FPRAS for all objects where…

Computational Geometry · Computer Science 2010-06-09 Karl Bringmann , Tobias Friedrich

Real-world knowledge is often organized as hierarchies such as product taxonomies, medical ontologies, and label trees, yet learning hierarchical representations is challenging due to asymmetric structure and noisy semantics. We introduce…

Machine Learning · Computer Science 2026-05-04 Sahil Mishra , Srinitish Srinivasan , Sourish Dasgupta , Tanmoy Chakraborty

Algorithmic decidability is established for two order-theoretic properties of downward closed subsets defined by finitely many obstructions in two infinite posets. The properties under consideration are: (a) being atomic, i.e. not being…

Combinatorics · Mathematics 2020-12-23 Matthew McDevitt , Nik Ruskuc

We study the following problem: with the power of postselection (classically or quantumly), what is your ability to answer adaptive queries to certain languages? More specifically, for what kind of computational classes $\mathcal{C}$, we…

Computational Complexity · Computer Science 2016-10-17 Lijie Chen

Large language model (LLM) architectures are often described as functionally hierarchical: Early layers process syntax, middle layers begin to parse semantics, and late layers integrate information. The present work revisits these ideas.…

Computation and Language · Computer Science 2025-01-14 Paul C. Bogdan

The infimal prefix-closed, controllable and observable superlanguage plays an essential role in the relationship between controllability, observability and co-observability -- the central notions of supervisory control theory. Existing…

Systems and Control · Computer Science 2017-03-16 Tomáš Masopust

Existing unsupervised hash learning is a kind of attribute-centered calculation. It may not accurately preserve the similarity between data. This leads to low down the performance of hash function learning. In this paper, a hash algorithm…

Machine Learning · Computer Science 2022-06-07 Shichao Zhang , Jiaye Li

In 2008, Bodirsky and Grohe showed that for every $\Pi_n^{\mathrm{P}}$-level of the Polynomial Hierarchy (PH) there are $\omega$-categorical Constraint Satisfaction Problems (CSPs) complete for this level. We show that, in fact, there are…

Logic in Computer Science · Computer Science 2026-04-28 Santiago Guzmán Pro , Jakub Rydval

We prove level-by-level upper and lower bounds on the strength of determinacy for finite differences of sets in the hyperarithmetical hierarchy in terms of subsystems of finite-and transfinite-order arithmetic, extending the…

Logic · Mathematics 2024-11-08 Juan Pablo Aguilera , Thibaut Kouptchinsky

We present a new algorithm to decide isomorphism between finite graded algebras. For a broad class of nilpotent Lie algebras, we demonstrate that it runs in time polynomial in the order of the input algebras. We introduce heuristics that…

Rings and Algebras · Mathematics 2019-05-06 Peter A. Brooksbank , E. A. O'Brien , James B. Wilson

Let $\cal{A}$ be the algebra of quaternions $\mathbb{H}$ or octonions $\mathbb{O}$. In this manuscript a new proof is given, based on ideas of Cauchy and D' Alembert, of the fact that an ordinary polynomial $f(t) \in {\cal{A}}\, [t]$ has a…

Rings and Algebras · Mathematics 2018-03-14 Takis Sakkalis

We prove that the isomorphism of scattered tree automatic linear orders as well as the existence of automorphisms of scattered word automatic linear orders are undecidable. For the existence of automatic automorphisms of word automatic…

Logic in Computer Science · Computer Science 2012-04-26 Dietrich Kuske

Given any square matrix or a bounded operator $A$ in a Hilbert space such that $p(A)$ is normal (or similar to normal), we construct a Banach algebra, depending on the polynomial $p$, for which a simple functional calculus holds. When the…

Functional Analysis · Mathematics 2015-06-03 Olavi Nevanlinna

We investigate a famous decision problem in automata theory: separation. Given a class of language C, the separation problem for C takes as input two regular languages and asks whether there exists a third one which belongs to C, includes…

Logic in Computer Science · Computer Science 2023-06-22 Thomas Place

We propose a distributional theory of how hypernymy -- the ``is-a'' relation between general and specific concepts -- is encoded geometrically in language representations. Starting from the empirically verified assumption that words closer…

Computation and Language · Computer Science 2026-05-25 Andres Nava , Matthieu Wyart

Avraham et al. [AFK+15] presented an alternative approach to parametric search, called \emph{bifurcation}, that performs faster under certain circumstances. Intuitively, when the underlying decider execution can be rolled back cheaply and…

Computational Geometry · Computer Science 2025-10-03 Sariel Har-Peled