Derek Ainslie Jackson, OBE, DFC, AFC, FRS[1] (23 June 1906 – 20 February 1982) was a British physicist.

He was educated at Rugby School and Trinity College, Cambridge, where he took a first in part I of the natural sciences tripos and graduated with honours in 1927.

For the rest of his life, Jackson, appointed a Fellow of the Royal Society in 1947, lived as a tax exile in Ireland, France and Switzerland.

A "rampant bisexual",[4][5] Jackson was married six times, and also lived for three years with Angela Culme-Seymour, the half-sister of Janetta Woolley, one of his wives.

The others included a daughter of Augustus John, Pamela Mitford (one of the Mitford sisters), a princess, and several femme fatales including Barbara Skelton (in whose obituary in the Independent is noted her remark that it was "not for love that (she) married Professor Jackson", he being identified as "the millionaire son of the founder of the News of the World").