5 papers
On the uniform positivity of -signature under reduction modulo
Shunsuke Takagi, Tatsuki Yamaguchi
Carvajal-Rojas, Schwede and Tucker asked whether the mod reductions of a complex klt type singularity have uniformly positive -signature for almost all primes . In this p…
Quasi--splitting versus log canonicity
Kenta Sato, Shunsuke Takagi, Shou Yoshikawa
In this paper, we investigate the relationship between quasi--splitting and log canonicity. We show that if a numerically -Gorenstein normal singularity is quasi-$F^…
Quasi--singularities and singularities in birational geometry
Tatsuro Kawakami, Shunsuke Takagi, Shou Yoshikawa
We give an overview of the theory of quasi--singularities, focusing on their connection with singularities in birational geometry.
On the behavior of adjoint ideals under pure morphisms
Shunsuke Takagi, Tatsuki Yamaguchi
We characterize adjoint ideal sheaves via ultraproducts and, utilizing this characterization, study their behavior under pure morphisms. In particular, given a pure morphism $f:Y \…
Threefolds of globally -regular type with nef anti-canonical divisor
Paolo Cascini, Tatsuro Kawakami, Shunsuke Takagi
As a special case of a conjecture by Schwede and Smith, we prove that a smooth complex projective threefold with nef anti-canonical divisor is weak Fano if it is of globally -re…