Diphthongs are micro-feet: Prominence and sonority in the nucleus

Abstract

In this paper we look at prominence in diphthongs and argue that diphthongs are structured in the same way metrical feet are. We propose a set of OT constraints that generates a typology of micro-feet. These are either iambic or trochaic or they are quality/sonority-sensitive with default to iamb or trochee in case of sonority plateaus (i.e., ui and iu). Crucially, we did not find any language with quantity-sensitive micro-feet. This gap is explained by the assumption that diphthongs are maximally bimoraic and that length in diphthongs is phonologically represented as mora sharing. For a quantity-sensitivity constraint targeting pairs of moras the two vowels in a diphthong are thus indistinguishable and prominence determination is left to sonority or foot form constraints which locate the prominence at an edge of the foot.