Twisted Sectors in Calabi-Yau Type Fermat Polynomial Singularities and Automorphic Forms

This paper demonstrates that twisted sectors in the vanishing cohomology of one-parameter deformations of Calabi-Yau type Fermat polynomial singularities, along with the genus zero Gromov-Witten generating series of the corresponding varieties, are components of automorphic forms for certain triangular groups, utilizing mixed Hodge structures, the Riemann-Hilbert correspondence, and genus zero mirror symmetry.

Dingxin Zhang, Jie ZhouMon, 09 Ma🔢 math

Inner Lipschitz approximation in o-minimal structures

This paper demonstrates that in o-minimal structures, every definable mapping that is Lipschitz with respect to the inner metric can be approximated by C1\mathscr{C}^1 (or C\mathscr{C}^\infty if the structure admits smooth cell decomposition) mappings with arbitrarily close derivative bounds, a result achieved through the construction of partitions of unity with sharp derivative estimates and extended to outer Lipschitz mappings.

Nhan Nguyen, Anna Valette, Guillaume ValetteMon, 09 Ma🔢 math

Oort's conjecture on automorphisms of generic supersingular abelian varieties

This paper proves Oort's conjecture that the automorphism group of a generic principally polarized supersingular abelian variety in characteristic pp is {±1}\{\pm 1\}, except for the specific cases of genus 2 or 3 with p=2p=2, while also providing an explicit description of the a=1a=1-locus in the corresponding Rapoport-Zink space and establishing analogous results for supersingular pp-divisible groups.

Eva ViehmannMon, 09 Ma🔢 math

Cohen-Macaulayness of Local Models via Shellability of the Admissible Set

This paper proves that augmented admissible sets in Iwahori-Weyl groups are dual EL-shellable, thereby resolving a conjecture of Görtz and establishing the Cohen-Macaulayness of special fibers for local models with parahoric level structure—including previously open cases in residue characteristic 2 and non-reduced root systems—through a characteristic-free, intrinsic construction that yields an explicit shelling and inductive building procedure.

Xuhua He, Felix Schremmer, Qingchao YuMon, 09 Ma🔢 math