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

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.