3 papers
math.RT2026
Rickard's question on standard derived equivalences
Wei Hu, Changchang Xi, Jin Zhang
In 1991 Rickard asked whether every derived equivalence of algebras over a common field is standard. We construct a series of examples of non-standard derived equivalences, and thu…
math.RT2026
Examples of nontrivial presilting objects in a singularity category
Changchang Xi, Jinbi Zhang
It was conjectured that no presilting objects exist in the singularity category of a finite-dimensional algebra over a field except the zero object. In this note, we give counterex…
math.RT2026
Singular equivalences and homological conjectures
Zhenxian Chen, Changchang Xi
The fact that each finite-dimensional algebra over a field is isomorphic to the centralizer of two matrices, has suggested to investigate representation theoretical problems of fin…