Thomas Charles Buckland McLeish FRS FRSC FInstP (1 May 1962 – 27 February 2023) was a British theoretical physicist.

[1] He was educated at Sevenoaks School in Kent and Emmanuel College, Cambridge[1] where he was awarded a Bachelor of Arts degree in 1984 (MA, 1987) and a PhD in 1987 for research on fluid dynamics.

[5] In February 2018, McLeish moved to the University of York to take up the newly created Chair in Natural Philosophy.

[7][8] He made significant advances in modelling the structure and properties of complex entangled molecules,[9] blends of substances that don't usually mix (multiphasic liquids like oil and water - see reptation and crazing).

[2] In 1993, he became a lay preacher in the Anglican Church, delivering sermons at St Michael le Belfrey, York.

In 2017, McLeish received the Sam Edwards Medal and Prize for "his sustained and outstanding contributions to the fields of molecular rheology, macromolecular biophysics and self-assembly".

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