I will discuss a new conjecture relating the cycle theory of the moduli space of principally polarized abelian varieties to the most mysterious tautological classes on the moduli space of curves of compact type (the classes which lie in the kernel of the Gorenstein pairing). The talk represent joint work with Canning, Drakengren, Feusi, Daniel Holmes, Iribar Lopez, Nesterov, Oprea, Schmitt, and Sun.
