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Related papers: Isomorphism relations on classes of c.e. algebras

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We reduce the isomorphism problem for undirected graphs without loops to the isomorphism problems for a class of finite dimensional $2$-step nilpotent Lie algebras over a field and for a class of finite $p$-groups. We show that the…

Group Theory · Mathematics 2020-08-03 Ruvim Lipyanski , Natalia Vanetik

Classifying isomorphism classes of group gradings on algebras presents a compelling challenge, particularly within the realms of non-simple and infinite-dimensional algebras, which have been relatively unexplored. This study focuses on a…

Rings and Algebras · Mathematics 2024-06-28 Waldeck Schützer , Felipe Yukihide Yasumura

In this paper, we give algorithms for determining the existence of isomorphism between two finite-dimensional Lie algebras and compute such an isomorphism in the affirrmative case. We also provide algorithms for determining algebraic…

Rings and Algebras · Mathematics 2021-02-23 Tuan A. Nguyen , Vu A. Le , Thieu N. Vo

We refine and advance the study of the local structure of idempotent finite algebras started in [A.Bulatov, The Graph of a Relational Structure and Constraint Satisfaction Problems, LICS, 2004]. We introduce a graph-like structure on an…

Logic in Computer Science · Computer Science 2016-01-28 Andrei A. Bulatov

Bell and Zhang have shown that if $A$ and $B$ are two connected graded algebras finitely generated in degree one that are isomorphic as ungraded algebras, then they are isomorphic as graded algebras. We exploit this result to solve the…

Quantum Algebra · Mathematics 2018-05-16 Jason Gaddis

A relational structure is a core, if all its endomorphisms are embeddings. This notion is important for computational complexity classification of constraint satisfaction problems. It is a fundamental fact that every finite structure has a…

Logic in Computer Science · Computer Science 2017-01-11 Manuel Bodirsky

We continue the study of the effective content of $K$-theory for C*-algebras, with a focus on AF algebras. We show that from a c.e. presentation of an AF algebra it is possible to compute a representation of the algebra as an inductive…

Operator Algebras · Mathematics 2026-02-09 Christopher J. Eagle , Isaac Goldbring , Timothy H. McNicholl

It is shown that if A is a stably finite C*-algebra and E is a countably generated Hilbert A-module, then E gives rise to a compact element of the Cuntz semigroup if and only if E is algebraically finitely generated and projective. It…

Operator Algebras · Mathematics 2008-11-07 Nathanial P. Brown , Alin Ciuperca

Let $R\subseteq E$ be two Lie conformal algebras and $Q$ be a given complement of $R$ in $E$. Classifying complements problem asks for describing and classifying all complements of $R$ in $E$ up to an isomorphism. It is known that $E$ is…

Rings and Algebras · Mathematics 2020-10-01 Yanyong Hong

If G and H are finitely generated, residually nilpotent metabelian groups, H is termed para-G if there is a homomorphism of G into H which induces an isomorphism between the corresponding terms of their lower central quotient groups. We…

Group Theory · Mathematics 2014-06-26 Gilbert Baumslag , Roman Mikhailov , Kent Orr

The construction of the C*-algebra associated to a directed graph $E$ is extended to incorporate a family $C$ consisting of partitions of the sets of edges emanating from the vertices of $E$. These C*-algebras $C^*(E,C)$ are analyzed in…

Operator Algebras · Mathematics 2011-07-12 P. Ara , K. R. Goodearl

We prove that the isomorphism relation for separable C$^*$-algebras, and also the relations of complete and $n$-isometry for operator spaces and systems, are Borel reducible to the orbit equivalence relation of a Polish group action on a…

Operator Algebras · Mathematics 2013-01-31 George A. Elliott , Ilijas Farah , Vern Paulsen , Christian Rosendal , Andrew S. Toms , Asger Törnquist

This work connects two mathematical fields - computational complexity and interval linear algebra. It introduces the basic topics of interval linear algebra - regularity and singularity, full column rank, solving a linear system, deciding…

Computational Complexity · Computer Science 2016-02-02 Jaroslav Horáček , Milan Hladík , Michal Černý

After a brief discussion of the computational complexity of Clifford algebras, we present a new basis for even Clifford algebra Cl(2m) that simplifies greatly the actual calculations and, without resorting to the conventional matrix…

Mathematical Physics · Physics 2009-06-25 Marco Budinich

computable functions are defined by abstract finite deterministic algorithms on many-sorted algebras. We show that there exist finite universal algebraic specifications that specify uniquely (up to isomorphism) (i) all abstract computable…

Logic in Computer Science · Computer Science 2007-05-23 J. V. Tucker , J. I. Zucker

As it follows from G\"odel's incompleteness theorems, any consistent formal system of axioms and rules of inference should imply a true unprovable statement. Actually, this fundamental principle can be efficiently applicable in…

Data Structures and Algorithms · Computer Science 2020-11-25 Roman Galay , Daniil Kalistratov

One way of studying a relational structure is to investigate functions which are related to that structure and which leave certain aspects of the structure invariant. Examples are the automorphism group, the self-embedding monoid, the…

Logic · Mathematics 2011-05-31 Manuel Bodirsky , Michael Pinsker

We work with the structure consisting of all computably enumerable (c.e.) sets ordered by set inclusion. The question we will partially address is which c.e.\ sets are autormorphic to low (or low$_2$ sets. Using work of Miller, we can see…

Logic · Mathematics 2015-12-29 Peter Cholak , Rachel Epstein

By combining well-known techniques from both noncommutative algebra and computational commutative algebra, we observe that an algorithmic approach can be applied to the study of irreducible representations of finitely presented algebras. In…

Rings and Algebras · Mathematics 2007-05-23 Edward S. Letzter

We provide isomorphism results for Hopf algebras that are obtained as graded twistings of function algebras on finite groups by cocentral actions of cyclic groups. More generally , we also consider the isomorphism problem for…

Quantum Algebra · Mathematics 2020-03-12 Julien Bichon , Maeva Paradis