Pfaffian of Appell's hypergeometric system in terms of the intersection form of twisted cohomology groups
arXiv:1502.00795
Abstract
We study a Pfaffian of the system of differential equations annihilating Appell's hypergeometric series by twisted cohomology groups associated with integrals representing solutions to this system. We simplify its connection matrix by the pull-back under a double cover of the complement of the singular locus. We express the simplified connection matrix in terms of the intersection form of the twisted cohomology groups.
23 pages, 1 figure