Zobrazeno 1 - 10
of 49
pro vyhledávání: '"Stein, Itamar"'
Autor:
Stein, Itamar
With every reduced $E$-Fountain semigroup $S$ which satisfies the generalized right ample condition we associate a category with partial composition $\mathcal{C}(S)$. Under some assumptions we prove an isomorphism of $\Bbbk$-algebras $\Bbbk S\simeq\B
Externí odkaz:
http://arxiv.org/abs/2404.08075
Autor:
Stein, Itamar
We study the generalized right ample identity, introduced by the author in a previous paper. Let $S$ be a reduced $E$-Fountain semigroup which satisfies the congruence condition. We can associate with $S$ a small category $\mathcal{C}(S)$ whose set o
Externí odkaz:
http://arxiv.org/abs/2209.07112
Autor:
Stein, Itamar
Let $S$ be a reduced $E$-Fountain semigroup. If $S$ satisfies the congruence condition, there is a natural construction of a category $\mathcal{C}$ associated with $S$. We define a $\Bbbk$-module homomorphism $\varphi:\Bbbk S\to\Bbbk\mathcal{C}$ (whe
Externí odkaz:
http://arxiv.org/abs/2104.02944
Autor:
Margolis, Stuart, Stein, Itamar
We study simple and projective modules of a certain class of Ehresmann semigroups, a well-studied generalization of inverse semigroups. Let $S$ be a finite right (left) restriction Ehresmann semigroup whose corresponding Ehresmann category is an EI-c
Externí odkaz:
http://arxiv.org/abs/2008.06852
Autor:
Adinayev, Arthur, Stein, Itamar
In this paper, we study a certain case of a subgraph isomorphism problem. We consider the Hasse diagram of the lattice $M_{k}$ (the unique lattice with $k+2$ elements and one anti-chain of length $k$) and want to find the maximal $k$ for which it is
Externí odkaz:
http://arxiv.org/abs/1910.02644
Autor:
Stein, Itamar
In this paper we study the representation theory of three monoids of partial functions on an $n$-set. The monoid of all order-preserving functions (i.e., functions satisfying $f(x)\leq f(y)$ if $x\leq y$) the monoid of all order-decreasing functions
Externí odkaz:
http://arxiv.org/abs/1812.01300
Autor:
Stein, Itamar
We prove that the global dimension of the complex algebra of the monoid of all partial functions on an n-set is $n-1$ for all $n\geq 1$. This is also the global dimension of the complex algebra of the category of all epimorphisms between subsets of a
Externí odkaz:
http://arxiv.org/abs/1801.00357
Autor:
Margolis, Stuart, Stein, Itamar
Publikováno v:
In Journal of Algebra 1 November 2021 585:176-206
Autor:
Stein, Itamar
$E$-Ehresmann semigroups are a commonly studied generalization of inverse semigroups. They are closely related to Ehresmann categories in the same way that inverse semigroups are related to inductive groupoids. We prove that under some finiteness con
Externí odkaz:
http://arxiv.org/abs/1512.06776
Autor:
Stein, Itamar
We give a new proof for the Littlewood-Richardson rule for the wreath product $F \wr S_{n}$ where $F$ is a finite group. Our proof does not use symmetric functions but more elementary representation theoretic tools. We also derive a branching rule fo
Externí odkaz:
http://arxiv.org/abs/1512.02170