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Related papers: Tight closure and plus closure in dimension two

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Border bases are traditionally restricted to 0-dimensional ideals due to the finiteness of the underlying order ideal. In this paper we extend the theory to homogeneous ideals of positive Krull dimension by introducing homogeneous border…

Commutative Algebra · Mathematics 2026-03-09 Cristina Bertone , Sofia Bovero

For a pair of finitely generated modules $M$ and $N$ over a codimension $c$ complete intersection ring $R$ with $\ell(M\otimes_RN)$ finite, we pay special attention to the inequality $\dim M+\dim N \leq \dim R +c$. In particular, we develop…

Commutative Algebra · Mathematics 2025-04-24 Petter Andreas Bergh , David A. Jorgensen , Peder Thompson

We show that the complex projective space has maximal degree (volume) among all n-dimensional Kahler-Einstein Fano manifolds admitting a holomorphic C^*-action with a finite number of fixed points. The toric version of this result,…

Differential Geometry · Mathematics 2012-04-06 Robert J. Berman , Bo Berndtsson

Let R be an integral domain and I a nonzero ideal of R. A sub-ideal J of I is a t-reduction of I if (JI^{n})_{t}=(I^{n+1})_{t} for some positive integer n. An element x in R is t-integral over I if there is an equation x^{n} + a_{1}x^{n-1}…

Commutative Algebra · Mathematics 2016-02-24 S. Kabbaj , A. Kadri

We classify fields having finitely many finite non-commutative (not necessarily central) division algebras over them. In the process, we introduce the notion of anti-closure of a field and also make comments on fields having a linear…

Rings and Algebras · Mathematics 2023-09-18 Snehinh Sen

The class of effectively closed infinite-genus surfaces, defining the completion of the domain of string perturbation theory, can be included in the category $O_G$, which is characterized by the vanishing capacity of the ideal boundary. The…

High Energy Physics - Theory · Physics 2009-11-10 Simon Davis

We show that any two homogeneous affine semigroups can be glued by embedding them suitably in a higher dimensional space. As a consequence, we show that the sum of their homogeneous toric ideals is again a homogeneous toric ideal, and that…

Commutative Algebra · Mathematics 2024-02-28 Philippe Gimenez , Hema Srinivasan

We provide a negative answer to an old question in tight closure theory by showing that the containment x^3y^3 \in (x^4,y^4,z^4)^* in K[x,y,z]/(x^7+y^7-z^7) holds for infinitely many but not for almost all prime characteristics of the field…

Commutative Algebra · Mathematics 2007-05-23 Holger Brenner , Mordechai Katzman

We prove extension of a di-bar-closed, smooth, form from the intersection of a pseudoconvex domain with a complex hyperplane to the whole domain. The extension form is di-bar-closed, has harmonic coefficients and its L^2-norm is estimated…

Complex Variables · Mathematics 2015-05-05 Luca Baracco , Stefano Pinton , Giuseppe Zampieri

We prove tight closure analogues of results of Watanabe about chains and families of integrally closed ideals.

Commutative Algebra · Mathematics 2007-05-23 Adela Vraciu

The notion of support provides an analogue of Stone duality, relating lattices to topological spaces. This note aims to explain in lattice theoretic terms what has been developed in the context of triangulated categories. In particular, the…

Category Theory · Mathematics 2023-07-25 Henning Krause

The aim of this article is to prove strong convergence results on the difference between the solution to highly oscillatory problems posed in thin domains and its two-scale expansion. We first consider the case of the linear diffusion…

Analysis of PDEs · Mathematics 2025-07-29 Virginie Ehrlacher , Arthur Lebée , Frédéric Legoll , Adrien Lesage

We prove the finiteness of leaps of modules of $m$-integrable derivations for algebras essentially of finite type and, more generally, for schemes essentially of finite type over an algebraically closed field of positive characteristic.…

Algebraic Geometry · Mathematics 2026-01-21 Takuya Miyamoto

We study the quantization of a holomorphic two-form coupled to a Yang-Mills field on special manifolds in various dimensions, and we show that it yields twisted supersymmetric theories. The construction determines ATQFT's (Almost…

High Energy Physics - Theory · Physics 2015-06-26 Laurent Baulieu , Alessandro Tanzini

We prove a technical result, showing that the existence of a closable unbounded dual system in the sense of Voiculescu is equivalent to the finiteness of free Fisher information. This approach allows one to give a purely operator-algebraic…

Operator Algebras · Mathematics 2007-05-23 Dimitri Shlyakhtenko

A complete classification of two-dimensional algebras over algebraically closed fields is provided

Rings and Algebras · Mathematics 2018-12-04 H. Ahmed , U. Bekbaev , I. Rakhimov

We find (completeness type) conditions on topological semilattices $X,Y$ guaranteeing that each continuous homomorphism $h:X\to Y$ has closed image $h(X)$ in $Y$.

General Topology · Mathematics 2021-11-01 Taras Banakh , Serhii Bardyla

A duality theorem of the bounded derived category of quasi-finite comodules over an artinian coalgebra is established. Let $A$ be a noetherian complete basic semiperfect algebra over an algebraically closed field, and $C$ be its dual…

Rings and Algebras · Mathematics 2010-10-07 J. -W. He , B. Torrecillas , F. Van Oystaeyen , Y. Zhang

We prove that if $B\subseteq A$ is an extension of finite dimensional algebras such that the projective dimension of $A/B$ as a $B$-bimodule is finite, if $A$ has finite finitistic dimension, then so does $B$. We exhibit examples…

Representation Theory · Mathematics 2023-06-06 John William MacQuarrie , Fernando dos Reis Naves

We use a generalization of a construction by Ziegler to show that for any field $F$ and any countable collection of countable subsets $A_i \subseteq F, i \in \calI \subset \Z_{>0}$ there exist infinitely many fields $K$ of arbitrary…

Logic · Mathematics 2011-05-16 Alexandra Shlapentokh , Carlos Videla