Takuro Abe
Published 2021-06-24Version 1
Terao's factorization theorem shows that if an arrangement is free, then its characteristic polynomial factors into the product of linear polynomials over the integer ring. This is not a necessary condition, but there are not so many non-free arrangements whose characteristic polynomial factors over the integer ring. On the other hand, the localization of a free arrangement is free, and its restriction is in many cases free, thus its characteristic polynomial factors. In this paper, we consider how their integer, or real roots behave.
On $A_1^2$ restrictions of Weyl arrangements
Multiple addition, deletion and restriction theorems for hyperplane arrangements
Why the characteristic polynomial factors
![QR code for arXiv:2106.12756 [math.CO]](http://oss.arxitics.com/images/favicon.svg)