Components and singularities of Quot schemes and varieties of commuting matrices

J Jelisiejew, K Šivic - Journal für die reine und angewandte …, 2022 - degruyter.com
We investigate the variety of commuting matrices. We classify its components for any
number of matrices of size at most 7. We prove that starting from quadruples of 8× 8 …

Phylogenetic invariants for the general Markov model of sequence mutation

ES Allman, JA Rhodes - Mathematical biosciences, 2003 - Elsevier
A phylogenetic invariant for a model of biological sequence evolution along a phylogenetic
tree is a polynomial that vanishes on the expected frequencies of base patterns at the …

Phylogenetic algebraic geometry

N Eriksson, K Ranestad, B Sturmfels… - Projective varieties with …, 2005 - degruyter.com
Phylogenetic algebraic geometry is concerned with certain complex projective algebraic
varieties derived from finite trees. Real positive points on these varieties represent …

A proof of the box conjecture for commuting pairs of matrices

J Irving, T Košir, M Mastnak - arxiv preprint arxiv:2403.18574, 2024 - arxiv.org
We prove the Box Conjecture for pairs of commuting nilpotent matrices, as formulated by
Iarrobino et al [28]. This describes the Jordan type of the dense orbit in the nilpotent …

[HTML][HTML] On the uniqueness and computation of commuting extensions

P Koiran - Linear Algebra and its Applications, 2024 - Elsevier
Abstract A tuple (Z 1,…, Z p) of matrices of size r× r is said to be a commuting extension of a
tuple (A 1,…, A p) of matrices of size n× n if the Z i pairwise commute and each A i sits in the …

On varieties of commuting triples III

K Šivic - Linear algebra and its applications, 2012 - Elsevier
The problem of irreducibility of the variety C (3, n) of triples of commuting n× n matrices is
equivalent to that whether each triple of commuting n× n matrices can be approximated …

[HTML][HTML] On varieties of commuting nilpotent matrices

NV Ngo, K Šivic - Linear Algebra and its Applications, 2014 - Elsevier
Let N (d, n) be the variety of all d-tuples of commuting nilpotent n× n matrices. It is well-
known that N (d, n) is irreducible if d= 2, if n⩽ 3 or if d= 3 and n= 4. On the other hand N (3, n) …

Approximating commuting operators

J Holbrook, M Omladič - Linear algebra and its applications, 2001 - Elsevier
Approximating commuting operators Page 1 Linear Algebra and its Applications 327 (2001)
131–149 www.elsevier.com/locate/laa Approximating commuting operators John Holbrook a …

On systems of commuting matrices, Frobenius Lie algebras and Gerstenhaber's Theorem

A Diatta, B Manga, A Mbaye - arxiv preprint arxiv:2002.08737, 2020 - arxiv.org
This work relates to three problems, the classification of maximal Abelian subalgebras
(MASAs) of the Lie algebra of square matrices, the classification of 2-step solvable …

Equivariant completions of affine spaces

I Arzhantsev, Y Zaitseva - arxiv preprint arxiv:2008.09828, 2020 - arxiv.org
We survey recent results on open embeddings of the affine space $\mathbb {C}^ n $ into a
complete algebraic variety $ X $ such that the action of the vector group $\mathbb {G} _a^ n …