Zobrazeno 1 - 10
of 94
pro vyhledávání: '"First, Uriya A."'
Autor:
Cantor, Omer, First, Uriya A.
Let $A$ be a finite dimensional algebra (possibly with some extra structure) over an infinite field $K$ and let $r\in\mathbb{N}$. The $r$-tuples $(a_1,\dots,a_r)\in A^r$ which fail to generate $A$ are the $K$-points of a closed subvariety $Z_r$ of th
Externí odkaz:
http://arxiv.org/abs/2410.04558
Autor:
First, Uriya, Williams, Ben
Suppose $A$ is an Azumaya algebra over a ring $R$ and $\sigma$ is an involution of $A$ extending an order-$2$ automorphism $\lambda:R\to R$. We say $\sigma$ is extraordinary if there does not exist a Brauer-trivial Azumaya algebra $\mathrm{End}_R(P)$
Externí odkaz:
http://arxiv.org/abs/2405.15260
Autor:
First, Uriya A., Kaufman, Tali
We study sheaves on posets, showing that cosystolic expansion of such sheaves can be derived from local expansion conditions of the sheaf and the poset (typically a high dimensional expander). When the poset at hand is a cell complex, a sheaf on it m
Externí odkaz:
http://arxiv.org/abs/2403.19388
Let $k$ be a field and let $G$ be an affine $k$-algebraic group. Call a $G$-torsor weakly versal for a class of $k$-schemes $\mathscr{C}$ if it specializes to every $G$-torsor over a scheme in $\mathscr{C}$. A recent result of the first author, Reich
Externí odkaz:
http://arxiv.org/abs/2401.04458
Autor:
First, Uriya A.
Let $G$ be a linear algebraic group over an infinite field $k$. Loosely speaking, a $G$-torsor over $k$-variety is said to be versal if it specializes to every $G$-torsor over any $k$-field. The existence of versal torsors is well-known. We show that
Externí odkaz:
http://arxiv.org/abs/2301.09426
Autor:
First, Uriya A., Kaufman, Tali
We expose a strong connection between good $2$-query locally testable codes (LTCs) and high dimensional expanders. Here, an LTC is called good if it has constant rate and linear distance. Our emphasis in this work is on LTCs testable with only $2$ qu
Externí odkaz:
http://arxiv.org/abs/2208.01778
Autor:
First, Uriya A., Kaufman, Tali
The Cheeger constant of a graph, or equivalently its coboundary expansion, quantifies the expansion of the graph. This notion assumes an implicit choice of a coefficient group, namely, $\mathbb{F}_2$. In this paper, we study Cheeger-type inequalities
Externí odkaz:
http://arxiv.org/abs/2208.01776
Autor:
First, Uriya A.
Let $(A,\sigma)$ be an Azumaya algebra with orthogonal involution over a ring $R$ with $2\in R^\times$. We show that if $(A,\sigma)$ admits an improper isometry, i.e., an element $a\in A$ with $\sigma(a)a=1$ and $\mathrm{Nrd}_{A/R}(a)=-1$, then the B
Externí odkaz:
http://arxiv.org/abs/2201.04921
Autor:
First, Uriya A.
Let $(A,\sigma)$ be an Azumaya algebra with involution over a regular ring $R$. We prove that the Gersten-Witt complex of $(A,\sigma)$ defined by Gille is isomorphic to the Gersten-Witt complex of $(A,\sigma)$ defined by Bayer-Fluckiger, Parimala and
Externí odkaz:
http://arxiv.org/abs/2102.06264
A theorem of O. Forster says that if $R$ is a noetherian ring of Krull dimension $d$, then any projective $R$-module of rank $n$ can be generated by $d+n$ elements. S. Chase and R. Swan subsequently showed that this bound is sharp: there exist exampl
Externí odkaz:
http://arxiv.org/abs/2012.07900