3 papers
math.AG2026
Lower Bounds on Essential Dimension for Congruence Covers of Mixed Shimura Varieties
Qi'An Chen
We use the fixed point method and toroidal compactifications to establish general lower bounds for the essential dimension of congruence covers $Γ' \backslash \mathcal{X}^0 \righta…
math.AG2025
A birational description of the minimal exponent
Qianyu Chen, Mircea Mustaţă
We give a description of the minimal exponent of a hypersurface using higher direct images of suitably twisted sheaves of log forms on a log resolution.
math.AG2024
Inversion of Adjunction for the minimal exponent
Qianyu Chen
We prove that the minimal exponent for local complete intersections satisfies an Inversion-of-Adjunction property. As a result, we also obtain the Inversion of Adjunction for highe…