Support τ-tilting modules over Morita context algebras: A bilateral approximation approach
Abstract
Let k be a field and let Λ=(A&N M&B)ϕ,ψ be a finite-dimensional Morita context algebra. We introduce a bilateral approximation construction which glues support τ-tilting modules over A and B by alternately correcting the two corner components through minimal approximations and pushouts. When this process terminates, it yields a support τ-tilting Λ-module with the prescribed componentwise torsion class. The one-sided case recovers Zhang's triangular-matrix construction, while the two-sided compatibility conditions give direct corner induction and, for radical-valued connecting maps, are also necessary, extending the Gao--Huang criterion. Examples show that the bilateral correction process can terminate even when neither one-sided compatibility condition is satisfied, while in other examples the process never terminates.
Related
- Relative Suspension and Higher Delooping for Support τ-Tilting Modules
- Support τ-tilting posets and Hochschild reconstruction for matrix centralizer algebras
- Self-Orthogonal τ-Tilting Modules and Tilting Modules III: Finitistic Dimension
- Self-Orthogonal τ-Tilting Modules and Tilting Modules II: Annihilator Separation
- Relative Derived Delooping Levels and τ-Tilting Modules
BibTeX
@misc{zhang2026support,
title = {{Support $τ$-tilting modules over Morita context algebras: A bilateral approximation approach}},
author = {Yingying Zhang},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.18746},
eprint = {2609.18746},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.18746},
}
RIS
TY - UNPB
TI - Support τ-tilting modules over Morita context algebras: A bilateral approximation approach
AU - Yingying Zhang
PY - 2026
DA - 2026/09/16
PB - arXiv
DO - 10.48550/arxiv.2609.18746
UR - https://arxiv.org/abs/2609.18746
AB - Let k be a field and let Λ=(A&N M&B)_ϕ,ψ be a finite-dimensional Morita context algebra. We introduce a bilateral approximation construction which glues support τ-tilting modules over A and B by alternately correcting the two corner components through minimal approximations and pushouts. When this process terminates, it yields a support τ-tilting Λ-module with the prescribed componentwise torsion class. The one-sided case recovers Zhang's triangular-matrix construction, while the two-sided compatibility conditions give direct corner induction and, for radical-valued connecting maps, are also necessary, extending the Gao--Huang criterion. Examples show that the bilateral correction process can terminate even when neither one-sided compatibility condition is satisfied, while in other examples the process never terminates.
ER -