activity
20042022
collaborators

10 papers

math.LO2022

Generically supercompact cardinals by forcing with chain conditions

Sakaé Fuchino, Hiroshi Sakai

A ccc-generically supercompact cardinal can be smaller than or equal to the continuum. On the other hand, such a cardinal still satisfies diverse largeness properties, like…

math.LO2021

Strong downward Löwenheim-Skolem theorems for stationary logics, III -- mixed support iteration

Sakaé Fuchino, André Ottenbreit Maschio Rodrigue, Hiroshi Sakai

Continuing [Fuchino, Ottenbreit and Sakai[9, 10]] and [Fuchino and Ottenbreit[11]], we further study reflection principles in connection with the Löwenheim-Skolem Theorems of stati…

math.LO2021

The first-order definability of generic large cardinals

Sakaé Fuchino, Hiroshi Sakai

We show that the notions of generic and Laver-generic supercompactness are first-order definable in the language of ZFC. This also holds for generic and Laver-generic (almost) huge…

math.LO2020

Strong downward Löwenheim-Skolem theorems for stationary logics, II -- reflection down to the continuum

Sakaé Fuchino, André Ottenbreit Maschio Rodrigues, Hiroshi Sakai

Continuing the previous paper, we study the Strong Downward Löwenheim-Skolem Theorems (SDLSs) of the stationary logic and their variations. It has been shown that the SDLS for the…

math.LO2019

Martin's Maximum and the Diagonal Reflection Principle

Sean Cox, Hiroshi Sakai

We prove that Martin's Maximum does not imply the Diagonal Reflection Principle for stationary subsets of .

math.LO2018

A variant of Shelah's characterization of Strong Chang's Conjecture

Sean Cox, Hiroshi Sakai

Shelah considered a certain version of Strong Chang's Conjecture, which we denote , and proved that it is equivalent to several statements, including the a…