English
Related papers

Related papers: Varieties generated by completions

200 papers

We classify all mutation-finite quivers with real weights. We show that every finite mutation class not originating from an integer skew-symmetrizable matrix has a geometric realization by reflections. We also explore the structure of…

Combinatorics · Mathematics 2022-05-04 Anna Felikson , Pavel Tumarkin

We characterize the class of RFD $C^*$-algebras as those containing a dense subset of elements that attain their norm under a finite-dimensional representation. We show further that this subset is the whole space precisely when every…

Operator Algebras · Mathematics 2017-07-10 Kristin Courtney , Tatiana Shulman

We observe that a finitely generated algebraic algebra R (over a field) is finite dimensional if and only if the associated graded ring grR is right noetherian, if and only if grR has right Krull dimension, if and only if grR satisfies a…

Rings and Algebras · Mathematics 2017-08-14 Edward S. Letzter

Algebras generated by strictly positive matrices are described up to similarity, including the commutative, simple, and semisimple cases. We provide sufficient conditions for some block diagonal matrix algebras to be generated by a set of…

Combinatorics · Mathematics 2020-07-29 N. A. Kolegov

We prove that among the finite dimensional algebras of finite representation type those that are string algebras are precisely the ones that have the property that the middle term of an arbitrary extension of indecomposable modules has at…

Representation Theory · Mathematics 2021-05-10 Mariano Suárez-Álvarez

Following ideas of Lawvere and Linton we prove that classical varieties are precisely the exact categories with a varietal generator. This means a strong generator which is abstractly finite and regularly projective. An analogous…

Category Theory · Mathematics 2024-02-23 Jiri Adamek

Over an algebraically closed field we classify all minimal representation-infinite algebras where the lattice of two-sided ideals is not distributive. As a consequence there are only finitely many isomorphism classes of minimal…

Representation Theory · Mathematics 2023-05-22 Klaus Bongartz

We show that bounded type implies finite type for a constructible subcategory of the module category of a finitely generated algebra over a field, which is a variant of the first Brauer-Thrall conjecture. A full subcategory is constructible…

Representation Theory · Mathematics 2025-07-31 Kevin Schlegel , Andres Fernandez Herrero

In this paper we consider some classical varieties of linear algebras over the field which has characteristic 0. For every considered variety we take a category of the finite generated free algebras of this variety. And for every this…

Rings and Algebras · Mathematics 2012-10-25 A. Tsurkov

We give a necessary and sufficient smoothness condition for the scheme parameterizing the n-dimensional representations of a finitely generated associative algebra over an algebraically closed field of characteristic zero. In particular,…

Algebraic Geometry · Mathematics 2015-10-26 Alessandro Ardizzoni , Federica Galluzzi , Francesco Vaccarino

We determine the representation-finiteness of $A\otimes B$, where both $A$ and $B$ are simply connected algebras with at least three simple modules.

Representation Theory · Mathematics 2024-04-30 Kengo Miyamoto , Qi Wang

We consider some special type extensions of an arbitrary Lie algebra, which we call universal extensions. We show that these extensions are in one-to-one correspondence with finite dimensional associative commutative algebras. We also…

Rings and Algebras · Mathematics 2007-05-23 A B Yanovski

We prove that the number of parameters defining a complex of projective modules over a finite dimensional algebra is upper semi-continuous in families of algebras. Supposing that every algebra is either derived tame or derived wild, we get…

Representation Theory · Mathematics 2007-05-23 Yuriy A. Drozd

We develop an analogue of universal algebra in which generating symbols are interpreted as relations. We prove a variety theorem for these relational algebraic theories, in which we find that their categories of models are precisely the…

Category Theory · Mathematics 2021-11-09 Chad Nester

We show that the finitistic dimension conjecture holds for all finite dimensional algebras if and only if, for all finite dimensional algebras, the finitistic dimension of an algebra being finite implies that the finitistic dimension of its…

Representation Theory · Mathematics 2024-03-06 Charley Cummings

The goal of this paper is to study the possible monoids appearing as the associated monoids of the initial algebra of a finitely generated homogeneous $\Bbbk$-subalgebra of a polynomial ring $\Bbbk[x_1,\ldots,x_n]$. Clearly, any affine…

Commutative Algebra · Mathematics 2024-04-03 Akihiro Higashitani , Koichiro Tani

We characterize completey (give a necessary and suffcient condition using special neat embeddings)for a relation algebra to belong to the amalgamation, strong amalgamation, and superamalgamation base of the class of representable algebras.…

Logic · Mathematics 2013-04-03 Tarek Sayed Ahmed

We investigate the representation and complete representation classes for algebras of partial functions with the signature of relative complement and domain restriction. We provide and prove the correctness of a finite equational…

Logic · Mathematics 2022-12-05 Célia Borlido , Brett McLean

The question of characterizing the (finite) representable relation algebras in a ``nice" way is open. The class $\mathbf{RRA}$ is known to be not finitely axiomatizable in first-order logic. Nevertheless, it is conjectured that ``almost…

Logic · Mathematics 2024-03-26 Jeremy F. Alm , Ashlee Bostic , Claire Chenault , Kenyon Coleman , Chesney Culver

Let V be a variety of not necessarily associative algebras, and A an inverse limit of nilpotent algebras A_i\in V, such that some finitely generated subalgebra S \subseteq A is dense in A under the inverse limit of the discrete topologies…

Rings and Algebras · Mathematics 2021-10-15 George M. Bergman