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We prove that P = NP implies #P = FP by exploiting the topological structure of 3SAT solution spaces. The argument proceeds via a dichotomy: any polynomial-time algorithm for 3SAT either operates without global knowledge of the…

Computational Complexity · Computer Science 2026-03-24 M. Alasli

We show that each level of the quantifier alternation hierarchy within FO^2[<] -- the 2-variable fragment of the first order logic of order on words -- is a variety of languages. We then use the notion of condensed rankers, a refinement of…

Logic in Computer Science · Computer Science 2015-05-13 Manfred Kufleitner , Pascal Weil

Extending the thoroughly studied theory of group stability, we study Ulam stability type problems for associative and Lie algebras; namely, we investigate obstacles to rank-approximation of almost solutions by exact solutions for systems of…

Rings and Algebras · Mathematics 2025-07-11 Tomer Bauer , Guy Blachar , Be'eri Greenfeld

Hierarchical text classification (HTC) assigns documents to multiple levels of a pre-defined taxonomy. Automated patent subject classification represents one of the hardest HTC scenarios because of domain knowledge difficulty and a huge…

Computation and Language · Computer Science 2025-10-09 Lekang Jiang , Wenjun Sun , Stephan Goetz

Suppose we are given a computably enumerable object arise from algorithmic randomness or computable analysis. We are interested in the strength of oracles which can compute an object that approximates this c.e. object. It turns out that,…

Logic · Mathematics 2019-12-09 Noam Greenberg , Joseph S. Miller , Andre Nies

In several classes of countable structures it is known that every hyperarithmetic structure has a computable presentation up to bi-embeddability. In this article we investigate the complexity of embeddings between bi-embeddable structures…

Logic · Mathematics 2021-11-30 Nikolay Bazhenov , Dino Rossegger , Maxim Zubkov

We compare four key hierarchies for solving Constrained Polynomial Optimization Problems (CPOP): Sum of Squares (SOS), Sum of Diagonally Dominant Polynomials (SDSOS), Sum of Nonnegative Circuits (SONC), and the Sherali Adams (SA)…

Data Structures and Algorithms · Computer Science 2019-03-13 Adam Kurpisz , Timo de Wolff

This paper studies the hierarchy of local minimums of a polynomial in the space. For this purpose, we first compute H-minimums, for which the first and second order optimality conditions are satisfied. To compute each H-minimum, we…

Optimization and Control · Mathematics 2014-11-26 Jiawang Nie

We revisit staircases for words and prove several exact as well as asymptotic results for longest left-most staircase subsequences and subwords and staircase separation number, the latter being defined as the number of consecutive maximal…

Combinatorics · Mathematics 2019-08-06 Toufik Mansour , Reza Rastegar , Alexander Roitershtein

Sorting and hashing are two completely different concepts in computer science, and appear mutually exclusive to one another. Hashing is a search method using the data as a key to map to the location within memory, and is used for rapid…

Data Structures and Algorithms · Computer Science 2007-05-23 William F. Gilreath

A topological hyperplane is a subspace of R^n (or a homeomorph of it) that is topologically equivalent to an ordinary straight hyperplane. An arrangement of topological hyperplanes in R^n is a finite set H such that k topological…

Combinatorics · Mathematics 2010-01-24 David Forge , Thomas Zaslavsky

Hierarchical vector field interpolation introduces a structured probabilistic framework for lexical representation, ensuring that word embeddings transition smoothly across a continuous manifold rather than being constrained to discrete…

Computation and Language · Computer Science 2025-03-27 Clive Pendleton , Ewan Harrington , Giles Fairbrother , Jasper Arkwright , Nigel Fenwick , Richard Katrix

Second-order polynomials generalize classical first-order ones in allowing for additional variables that range over functions rather than values. We are motivated by their applications in higher-order computational complexity theory,…

Logic in Computer Science · Computer Science 2023-05-23 Donghyun Lim , Martin Ziegler

We extend classical methods of computational complexity to the realm of distributed computing, where they sometimes prove more effective than in their original context. Our focus is on decision problems in the LOCAL model, a setting in…

Distributed, Parallel, and Cluster Computing · Computer Science 2025-09-08 Fabian Reiter

We investigate the complexity of the separation problem associated to classes of regular languages. For a class C, C-separation takes two regular languages as input and asks whether there exists a third language in C which includes the…

Formal Languages and Automata Theory · Computer Science 2018-10-23 Thomas Place , Marc Zeitoun

We introduce a hierarchy of fast-growing complexity classes and show its suitability for completeness statements of many non elementary problems. This hierarchy allows the classification of many decision problems with a non-elementary…

Computational Complexity · Computer Science 2016-02-05 Sylvain Schmitz

We look at concatenation hierarchies of classes of regular languages. Each such hierarchy is determined by a single class, its basis: level $n$ is built by applying the Boolean polynomial closure operator (BPol), $n$ times to the basis. A…

Formal Languages and Automata Theory · Computer Science 2024-01-30 Thomas Place , Marc Zeitoun

SEQUITUR is an algorithm that infers a hierarchical structure from a sequence of discrete symbols by replacing repeated phrases with a grammatical rule that generates the phrase, and continuing this process recursively. The result is a…

Artificial Intelligence · Computer Science 2009-09-25 C. G. Nevill-Manning , I. H. Witten

It is well-known that the first order Peano axioms PA have a continuum of non-isomorphic countable models. The question, how close to being isomorphic such countable models can be, seems to be less investigated. A measure of closeness to…

Logic · Mathematics 2022-08-30 Tapani Hyttinen , Jouko Väänänen

A conjecture of Jozsa (arXiv:quant-ph/0508124) states that any polynomial-time quantum computation can be simulated by polylogarithmic-depth quantum computation interleaved with polynomial-depth classical computation. Separately, Aaronson…

Quantum Physics · Physics 2020-07-07 Matthew Coudron , Sanketh Menda