The thesis, Identity conditions on ellipsis, argues for a new perspective on the identity requirement underpinning ellipsis in natural language. Specifically, it argues that identity under ellipsis is irreducibly syntactic – at least in part – but the way this syntactic component works is different than previously thought. Instead of requiring simple identity of structures/features, the requirement is one of non-distinctness. Thus, for example, a privative feature present in the antecedent but not in the ellipsis site (or vice versa) does not constitute a violation of identity. Nor does a functional projection present in one but not the other.
The thesis builds its initial case on the basis of voice mismatches under sluicing in the Mayan language Kaqchikel, which Rodrigo has done extensive fieldwork on in the Guatemalan highlands. Unlike the pattern familiar from English, Kaqchikel bans certain voice mismatches, but allows others. Rodrigo shows, first, that the Kaqchikel construction in question is indeed unquestionably an instance of sluicing per se. And second, that the empirical pattern in question can only be captured by the aforementioned kind of identity condition, one based on featural non-distinctness.
The empirical scope is then expanded to include gender mismatch in nominal ellipsis (in both argument and predicate positions), as well as the complicated landscape of mismatches in the Mittelfeld under sluicing, some of which are tolerated and some of which, contrary to previous claims in the literature, are not.
(UPDATE: The thesis is now available on lingbuzz.)