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Context-Free Languages and Associative Algebras with Algebraic Hilbert Series
P. 279–289.
La Scala R., Piontkovski D.
In this paper, homological methods together with the theory of formal languages of theoretical computer science are proved to be effective tools to determine the growth and the Hilbert series of an associative algebra. Namely, we construct a class of finitely presented associative algebras related to a family of context-free languages. This allows us to connect the Hilbert series of these algebras with the generating functions of such languages. In particular, we obtain a class of finitely presented graded algebras with non-rational algebraic Hilbert series.
In book
Association for Computational Linguistics, 2022.
D. A. Matveev, Siberian Mathematical Journal 2025 Vol. 66 No. 3 P. 715–727
We consider an affine algebraic variety with a torus action of complexity one. It is known
that in this case homogeneous locally nilpotent derivations on the algebra of functions of this variety
are defined in terms of a polyhedral divisor. In the present paper, a formula is obtained for multiple
commutators of two homogeneous locally nilpotent derivations with ...
Added: July 21, 2025
Shmatko N., Маркова Ю. В., Социологический журнал 2025 Т. 31 № 1 С. 110–123
The article deals with the history and interpretation of Pierre Bourdieu’s concept of “social space”.
With the help of the concept, Bourdieu described a set of interrelated social phenomena that support
and reflect each other. He defined social space as a multidimensional distribution of agents (individual
or collective) over objective positions determined by the distribution of effective resources ...
Added: May 23, 2025
Pogrebkov A., Теоретическая и математическая физика 2023 Т. 217 № 3 С. 577–584
We consider some generalizations of a (2 + 1)-dimensional Davey–Stewartson-type equation. In particular,
we propose a dynamical system that does not admit an explicit formulation in terms of differential equations, but needs an additional independent variable. ...
Added: January 24, 2025
Trushin A., Математические заметки 2023 Т. 113 № 5 С. 780–784
It is known that the group of automorphisms of the algebra of polynomials in three variables is not generated by elementary automorphisms. In the article, a system of generators is constructed for the group of automorphisms preserving the nontrivial grading by integers. ...
Added: September 18, 2024
A. N. Trushin, Mathematical notes 2023 Vol. 113 No. 5 P. 736–740
It is known that the group of automorphisms of the algebra of polynomials in three variables is not generated by elementary automorphisms. In the article, a system of generators is constructed for the group of automorphisms preserving the nontrivial grading by integers. ...
Added: September 18, 2024
Ignatyev Mikhail, Kaygorodov I., Popov Y., Revista Matemática Complutense 2022 Vol. 35 No. 3 P. 907–922
We give a geometric classification of complex n-dimensional 2-step nilpotent (all, commutative and anticommutative) algebras. Namely, it has been found the number of irreducible components and their dimensions. As a corollary, we have a geometric classification of complex 5-dimensional nilpotent associative algebras. In particular, it has been proven that this variety has 11 irreducible components ...
Added: February 19, 2024
Dimitrov G., Katzarkov L. V., International Mathematics Research Notices 2022 Vol. 2022 No. 17 P. 13317–13395
In our previous paper, viewing D-b(K(l)) as a noncommutative curve, where K(l) is the Kronecker quiver with l-arrows, we introduced categorical invariants via counting of noncommutative curves. Roughly, these invariants are sets of subcategories in a given category and their quotients. The noncommutative curve-counting invariants are obtained by restricting the subcategories to be equivalent to D-b(K(l)). The general definition, however, defines a larger class of invariants and many of them behave ...
Added: May 22, 2023
Arzhantsev I., Вестник Московского университета. Серия 1: Математика. Механика 1994 № 4 С. 18–23
В работе изучается конструкция Нагаты-Стейнберга, с помощью которой был построен первый контрпример к 14-й проблеме Гильберта о конечной порожденности алгебры инвариантов линейной алгебраической группы. Показано, что при определенных условиях алгебры, возникающие в рамках этой конструкции, являются конечно порожденными. ...
Added: February 19, 2023
Lopatkin V., Journal of Algebra 2019 Vol. 520 P. 59–89
In this paper, we describe the K-module HH1(LK(Γ)) of outer derivations of the Leavitt path algebra LK(Γ) of a row-finite graph Γ with coefficients in an associative commutative ring K with unit. We explicitly describe a set of generators of HH1(LK(Γ)) and relations among them. We also describe a Lie algebra structure of outer derivation algebra of the Toeplitz algebra. We prove that every derivation of a ...
Added: October 29, 2021
Rubtsov A. A., , in: Developments in Language Theory: 25th International Conference, DLT 2021, Porto, Portugal, August 16–20, 2021, Proceedings.: Switzerland: Springer International Publishing, 2021. P. 342–354.
A d-limited automaton is a nondeterministic Turing machine that uses only the cells with the input word (and end-markers) and rewrites symbols only in the first d visits. This model was introduced by T. Hibbard in 1967 and he showed that d-limited automata recognize context-free languages for each 𝑑⩾2d⩾2. He also proved that languages recognizable by deterministic d-limited automata form a hierarchy ...
Added: September 28, 2021
Rumynin D., Taylor J., Linear Algebra and its Applications 2021 Vol. 610 P. 135–168
We use the structure of finite-dimensional graded algebras to develop the theory of antilinear representations of finite C_2-graded groups. A finite C_2-graded group is a finite group with a subgroup of index 2. In this theory the subgroup acts linearly, while the other coset acts antilinearly. We introduce antilinear blocks, whose structure is a crucial ...
Added: September 7, 2021
Piontkovski D., La Scala R., Springer INdAM Series 2021 Vol. 44 P. 279–289
In this paper, homological methods together with the theory of formal languages of theoretical computer science are proved to be effective tools to determine the growth and the Hilbert series of an associative algebra. Namely, we construct a class of finitely presented associative algebras related to a family of context-free languages. This allows us to ...
Added: April 3, 2021
Gayfullin S., Journal of Algebra 2021 No. 573 P. 364–392
In 2007, Dubouloz introduced Danielewski varieties. Such varieties generalize Danielewski surfaces and provide counterexamples to generalized Zariski cancellation problem in arbitrary dimension. In the present work we describe the automorphism group of a Danielewski variety. This result is a generalization of a description of automorphisms of Danielewski surfaces due to Makar-Limanov. ...
Added: February 6, 2021