Glottalic theory

Glottalic theory proposes that Proto-Indo-European’s traditionally reconstructed voiced-stop series was ejective, while its traditionally voiceless stops were voiced.

Ejective consonant: A consonant produced with a closed glottis, whose upward movement compresses air in the mouth. The theory identifies Proto-Indo-European’s disputed voiced series as ejectives.
Thomas Gamkrelidze: A Georgian linguist who co-developed a glottalic interpretation of Proto-Indo-European stops. His work with Ivanov helped formulate the influential version of the theory.
Proto-Indo-European: The unattested ancestor language reconstructed as the source of the Indo-European language family. Glottalic theory proposes a different stop inventory for this reconstructed language.
Indo-European sound laws: Regular sound changes that account for systematic correspondences among Indo-European languages. Any revised stop inventory must fit the established branch-specific sound correspondences.
Glottalic airstream mechanism: A speech airflow mechanism in which the larynx moves to compress or rarefy air above the glottis. It supplies the airflow process behind the theory’s proposed stop series.
Vyacheslav Ivanov: A Soviet and Russian linguist who co-developed a glottalic interpretation of Proto-Indo-European stops. His joint proposal with Gamkrelidze brought the theory into broader Indo-European scholarship.
Traditional Proto-Indo-European phonology: The conventional reconstruction of Proto-Indo-European sounds, including a three-way stop contrast with voiced stops. It assigns the disputed series voicing rather than the ejective articulation proposed here.
Indo-European phonological typology: The comparison of reconstructed Indo-European sound patterns with cross-linguistic distributions of phonological systems. The theory was partly motivated by the unusual typological profile of the traditional reconstruction.
Indo-European consonant system: The reconstructed set of consonant contrasts in Proto-Indo-European, including stops, resonants, and laryngeals. The theory reassigns the phonation types in this reconstructed system.
Indo-European and the Indo-Europeans: A 1995 English-language synthesis by Thomas Gamkrelidze and Vyacheslav Ivanov on Indo-European language and prehistory. It presents the co-authors’ mature case for the glottalic reconstruction.

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