Some remarks on Gopakumar-Vafa invariants
Abstract
Description
We show that Gopakumar-Vafa invariants can be expressed in terms of the cohomology ring of moduli space of D-branes without reference to the sl_2 \times sl_2 action. We also give a simple construction of this action.
9 pages, some additions and clarifications, minor changes
9 pages, some additions and clarifications, minor changes