7 papers
Complement minimally non-totally unimodular matrices
Suyoung Choi, Mathieu Vallée
We prove that, up to row and column permutations and complement operations, the only complement minimally non-totally unimodular matrices are the cycle matrices and . Th…
On the toric lifting properties for simplicial -spheres
Suyoung Choi, Yuanxin Guan, Hyeontae Jang +1
We study the lifting problem for mod characteristic maps over simplicial -spheres. Using a bad-block partition of the universal complex , we prove an avoi…
Enumerating Toric-Colorable Seeds of Picard Number Five via Binary Matroids
Suyoung Choi, Mathieu Vallée
We introduce a binary matroid framework for the enumeration of mod toric-colorable seeds of fixed Picard number. Working with binary matroids up to isomorphism, we organize the…
Small covers as pullbacks from the simplex
Suyoung Choi, Hyeontae Jang, Younghan Yoon
We introduce and study small covers that are pullbacks from the simplex, extending pullbacks from the linear model. Our main result gives several equivalent characterizations of th…
Complete non-singular toric varieties with Picard number 4
Suyoung Choi, Hyeontae Jang, Mathieu Vallée
We classify all complete non-singular toric varieties with Picard number four via a combinatorial framework based on fanlike simplicial spheres and characteristic maps. This classi…
Stellar subdivisions, wedges and Buchstaber numbers
Suyoung Choi, Hyeontae Jang
A seed is a PL sphere that is not obtainable by a wedge operation from any other PL sphere. In this paper, we study two operations on PL spheres, known as the stellar subdivision a…