Glottalic theory

The glottalic theory holds that Proto-Indo-European had ejective stops, *pʼ *tʼ *kʼ, instead of the plain voiced ones, *b *d *ɡ, hypothesized by traditional Proto-Indo-European phonological reconstructions.

A forerunner of the theory was proposed by the Danish linguist Holger Pedersen in 1951, but he did not involve glottalized sounds. While early linguists such as André Martinet and Morris Swadesh had seen the potential of substituting glottalic sounds for the supposed plain voiced stops of Proto-Indo-European, the proposal remained speculative until fully fleshed-out theories were simultaneously but independently published in 1973 by Paul Hopper of the United States in the journal Glossa and by Tamaz V. Gamkrelidze and Vyacheslav Ivanov of the Soviet Union in the journal Phonetica in 1972.

The glottalic theory "enjoyed a not insignificant following for a time, but it has been rejected by most Indo-Europeanists." The most recent publication supporting it is Allan R. Bomhard (2008 and 2011), in a discussion of the controversial Nostratic hypothesis, and its most vocal proponents today are historical linguists at the University of Leiden. An earlier supporter, Theo Vennemann, has abandoned the glottalic theory because of incompatibilities between it and his theory of the Semitic origins of Germanic and Celtic (Vennemann 2006).

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