Publications and Preprints
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Descending strong generation in algebraic geometry (with P. Lank and K. Manali Rahul), 2025.
arXiv |
▸ Abstract
▸ We formalize the main approach for showing Zariski descent-type statements for strong generation of triangulated categories associated to algebro-geometric objects.
This recovers various known statements in the literature.
As applications we show that strong generation for the singularity category of a Noetherian separated scheme is Zariski local
and obtain a strong generation result for the bounded derived category of a Noetherian concentrated algebraic stacks with finite diagonal.
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Descent and generation for noncommutative coherent algebras over schemes (with P. Lank and K. Manali Rahul), 2024.
arXiv |
▸ Abstract
▸ Our work shows forms of descent, in the fppf, h and \'{e}tale topologies, for strong generation of the bounded derived category of a noncommutative coherent algebra over a scheme.
Even for (commutative) schemes this yields new perspectives.
As a consequence we exhibit new examples where these bounded derived categories admit strong generators.
We achieve our main results by leveraging the action of the scheme on the coherent algebra, allowing us to lift statements into the noncommutative setting.
In particular, this leads to interesting applications regarding generation for Azumaya algebras.
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Approximability and Rouquier dimension for noncommutative algebras over schemes (with P. Lank and K. Manali Rahul), 2024.
arXiv |
▸ Abstract
▸ This work is concerned with approximability (à la Neeman) and Rouquier dimension for triangulated categories associated to noncommutative algebras over schemes.
Amongst other things, we establish that the category of perfect complexes of a Noetherian quasi-coherent algebra over a separated Noetherian scheme is strongly generated if, and only if,
there exists an affine open cover where the algebra has finite global dimension.
As a consequence, we solve an open problem posed by Neeman.
Further, as a first application, we study the existence of generators for Azumaya algebras.
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Categorical resolutions of filtered schemes, J. Noncommut. Geom., 2024.
arXiv |
Journal |
▸ Abstract
▸ We give an alternative proof of the theorem by Kuznetsov and Lunts, stating that any separated scheme of finite type over a field of characteristic zero admits a categorical resolution of singularities.
Their construction makes use of the fact that every variety (over a field of characteristic zero) can be resolved by a finite sequence of blow-ups along smooth centres.
We merely require the existence of (projective) resolutions.
To accomplish this we put the $\mathcal{A}$-spaces of Kuznetsov and Lunts in a different light, viewing them instead as schemes endowed with finite filtrations.
The categorical resolution is then constructed by gluing together differential graded categories obtained from a hypercube of finite length filtered schemes.
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A note on affine cones over Grassmannians and their stringy $E$-functions, Proc. Amer. Math. Soc., 2023.
arXiv |
Journal |
▸ Abstract
▸ We compute the stringy $E$-function of the affine cone over a Grassmannian.
If the Grassmannian is not a projective space then its cone does not admit a crepant resolution.
Nonetheless the stringy $E$-function is sometimes a polynomial and in those cases the cone admits a noncommutative crepant resolution.
This raises the question as to whether the existence of a noncommutative crepant resolution implies that the stringy $E$-function is a polynomial.