Tait, Peter Guthrie (1831–1901)

British mathematician and physicist. In mathematics he developed Hamilton's theory of quaternions and contributed to mathematical physics, especially in the Treatise on Natural Philosophy (1867),written in collaboration with William Thomson. His physical researches and experiments were mainly in connection with thermodynamics and thermoelectricity. He collaborated with Balfour Stewart in writing The Unseen Universe, or Physical Speculation on a Future State (1875) and Paradoxical Philosophy (1878).

Tait was born in Dalkeith, Midlothian, Scotland. He was educated at Edinburgh Academy, Edinburgh University, and Peterhouse, Cambridge University. In 1854 he was appointed to the professorship of mathematics at Queen's College (now Queen's University), Belfast. He moved on to Edinburgh University in 1860 to occupy the chair of natural philosophy.