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Related papers: A proof of extension conjecture

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In this paper, our primary focus is on investigating the extension dimensions of syzygy module categories associated with Artin algebras, particularly under various equivalences. We demonstrate that, for sufficiently large $i$, the $i$-th…

Representation Theory · Mathematics 2026-05-08 Junling Zheng , Lulu Tian , Qianyu Shu

In this paper we study the behaviour of modules over finite dimensional algebras whose endomorphism algebra is a division ring. We show that there are finitely many such modules in the module category of an algebra if and only if the length…

Representation Theory · Mathematics 2020-06-09 Sibylle Schroll , Hipolito Treffinger

Let A be a finite dimensional associative algebra over an algebraically closed field with a simple module S of finite projective dimension. The strong no loop conjecture says that this implies Ext(S,S)=0, i.e. that the quiver of A has no…

Representation Theory · Mathematics 2010-12-15 Denis Skorodumov

We prove a structure theorem for Lie n-algebras possessing an invariant inner product. We define the notion of a double extension of a metric Lie n-algebra by another Lie n-algebra and prove that all metric Lie n-algebras are obtained from…

Representation Theory · Mathematics 2008-06-24 José Figueroa-O'Farrill

Let $\Lambda$ be an artin algebra. We are going to consider full subcategories of $\mod\Lambda$ closed under finite direct sums and under submodules with infinitely many isomorphism classes of indecomposable modules. The main result asserts…

Representation Theory · Mathematics 2010-09-07 Claus Michael Ringel

Let $B\subset A$ be a left or right bounded extension of finite dimensional algebras. We use the Jacobi-Zariski long nearly exact sequence to show that $B$ satisfies Han's conjecture if and only if $A$ does, regardless if the extension…

K-Theory and Homology · Mathematics 2022-02-07 Claude Cibils , Marcelo Lanzilotta , Eduardo N. Marcos , Andrea Solotar

Let C be a finite dimensional algebra with B a split extension by a nilpotent bimodule E. We provide a short proof to a conjecture by Assem and Zacharia concerning properties of mod B inherited by mod C. We show if B is a tilted algebra,…

Representation Theory · Mathematics 2019-10-16 Stephen Zito

The codimension-three conjecture states that any regular holonomic module extends uniquely beyond an analytic subset with codimension equal to or larger than three. We give a proof of this conjecture.

Algebraic Geometry · Mathematics 2013-07-30 Masaki Kashiwara , Kari Vilonen

We investigate bicomplex analogues of fundamental notions from classical algebraic number theory. In particular, we show that the primitive element theorem admits a natural generalization to bicomplex extensions, giving rise to two distinct…

Number Theory · Mathematics 2026-02-17 Hichem Gargoubi , Sayed Kossentini

We calculate the first extension groups for finite-dimensional simple modules over an arbitrary generalized current Lie algebra, which includes the case of loop Lie algebras and their multivariable analogs.

Representation Theory · Mathematics 2009-08-30 Ryosuke Kodera

We extend the definition of an extension of a right Hilbert module to the setting of Hilbert bimodules and show that an extension of Hilbert bimodules induces an extension of Cuntz-Pimsner algebras. We also study the Cuntz-Pimsner algebra…

Operator Algebras · Mathematics 2011-05-10 David Robertson

A main purpose of this paper is to prove that the class of finite dimensional algebras which verify Han's conjecture is closed under split bounded extensions.

K-Theory and Homology · Mathematics 2021-03-01 Claude Cibils , Marcelo Lanzilotta , Eduardo N. Marcos , Andrea Solotar

In this note we compare the a-invariant of a homogeneous algebra B to the a-invariant of a subalgebra A. In particular we show that if $A \subset B$ is a finite homogeneous inclusion of standard graded domains over an algebraically closed…

Commutative Algebra · Mathematics 2011-05-31 Andrew Kustin , Claudia Polini , Bernd Ulrich

The notion of essential submodules and essential extensions of modules are extended to groups (typically nonabelian), and several necessary and sufficient conditions for a group to possess a proper essential subgroup are investigated.…

Group Theory · Mathematics 2024-07-30 Sourav Koner , Biswajit Mitra

To any periodic module over any algebra, this paper introduces an associated trivial extension DG-algebra T. After first passing to a strictly unital $A_\infty$-minimal model, it then constructs a particular $A_\infty$-algebra N, called the…

Algebraic Geometry · Mathematics 2025-01-24 Joseph Karmazyn , Emma Lepri , Michael Wemyss

We consider a class of extensions of associative algebras, which we refer to as ``strongly proj-bounded extensions''. We prove that the finiteness of the left global dimension and the support of the Hochschild homology is preserved by…

K-Theory and Homology · Mathematics 2025-01-07 Kostiantyn Iusenko , John W. MacQuarrie

For Nakayama algebras $A$, we prove that in case $Ext_A^1(M,M) \neq 0$ for an indecomposable $A$-module $M$, we have that the projective dimension of $M$ is infinite. As an application we give a new proof of a classical result from…

Representation Theory · Mathematics 2023-08-30 Rene Marczinzik

Let $F$ be a totally real field of degree $n$ and $p$ an odd prime. We prove the $p$-part of the integral Gross--Stark conjecture for the Brumer--Stark $p$-units living in CM abelian extensions of $F$. In previous work, the first author…

Number Theory · Mathematics 2023-07-26 Samit Dasgupta , Mahesh Kakde

We prove several basic extension theorems for reductive group schemes. We also prove that each Lie algebra with a perfect Killing form over a commutative $\dbZ$-algebra, is the Lie algebra of an adjoint group scheme.

Number Theory · Mathematics 2016-02-24 Adrian Vasiu

Over a commutative Noetherian ring, we show that the Auslander-Reiten conjecture holds true for the class of (finitely generated) modules whose dual has finite complete intersection dimension. We provide another result that validates the…

Commutative Algebra · Mathematics 2026-03-16 Dipankar Ghosh , Mouma Samanta