3 problems

Let ${\mathcal D}$ be an arrangement of hyperplanes on a projective space, and let its combinatorics mean the incidence data of the arrangement. The arrangement is free when the du…

Let $\mathcal{H}=\{H_{1},\ldots,H_{\ell}\}$ be an arrangement of $\ell\geq n+2$ hyperplanes on $\mathbf{P}^{n}$. Assume that the logarithmic bundle…

Let $\Phi$ be an irreducible crystallographic root system of rank $m$, let $k\geq 1$ and $j\geq 0$, and set … For a logarithmic bundle $T_{\mathcal{A}}$, write…