Cluster categories and rational curves

Z Hua, B Keller - arXiv preprint arXiv:1810.00749, 2018 - arxiv.org
We study rational curves on smooth complex Calabi--Yau threefolds via noncommutative
algebra. By the general theory of derived noncommutative deformations due to Efimov …

Singular Hochschild cohomology via the singularity category

B Keller - Comptes Rendus. Mathématique, 2018 - comptes-rendus.academie-sciences …
Nous montrons que la cohomologie de Hochschild singulière (cohomologie de Tate–
Hochschild) d'une algèbre A est isomorphe, en tant qu'algèbre graduée, à la cohomologie …

String topology in three flavors

F Naef, M Rivera, N Wahl - EMS Surveys in Mathematical Sciences, 2023 - ems.press
We describe two major string topology operations, the Chas–Sullivan product and the
Goresky–Hingston coproduct, from geometric and algebraic perspectives. The geometric …

Differential graded enhancements of singularity categories

XW Chen, Z Wang - arXiv preprint arXiv:2312.12138, 2023 - arxiv.org
The singularity category of a ring detects the homological singularity of the given ring, and
appears in many different contexts. We describe two different dg enhancements of the …

Box operads and higher Gerstenhaber brackets

HD Van, L Hermans, W Lowen - arXiv preprint arXiv:2305.20036, 2023 - arxiv.org
We introduce a symmetric operad $\square p $(" box-op") which describes a certain calculus
of rectangular labeled``boxes''. Algebras over $\square p $, which we call box operads, have …

Characterization of eventually periodic modules in the singularity categories

S Usui - Journal of Pure and Applied Algebra, 2022 - Elsevier
The singularity category of a ring makes only the modules of finite projective dimension
vanish among the modules, so that the singularity category is expected to characterize a …

The dg Leavitt algebra, singular Yoneda category and singularity category

XW Chen, Z Wang, B Keller, Y Wang - Advances in Mathematics, 2024 - Elsevier
For any finite dimensional algebra Λ given by a quiver with relations, we prove that its dg
singularity category is quasi-equivalent to the perfect dg derived category of a dg Leavitt …

Invariance of the Gerstenhaber algebra structure on Tate-Hochschild cohomology

Z Wang - Journal of the Institute of Mathematics of Jussieu, 2021 - cambridge.org
Keller proved in 1999 that the Gerstenhaber algebra structure on the Hochschild
cohomology of an algebra is an invariant of the derived category. In this paper, we adapt his …

Invariance of the Goresky–Hingston algebra on reduced Hochschild homology

M Rivera, Z Wang - Proceedings of the London Mathematical …, 2022 - Wiley Online Library
We prove that two quasi‐isomorphic simply connected differential graded associative
Frobenius algebras have isomorphic Goresky–Hingston algebras on their reduced …

Singular equivalence and singular locus

L Liu, J Zeng - arXiv preprint arXiv:2403.13637, 2024 - arxiv.org
For a commutative Gorenstein Noetherian ring $ R $, we construct an affine scheme $ X $
solely from singularity category $ D_ {sg}(R) $ of $ R $ such that there is a finite surjective …