Already at the time of his doctoral work he studied the influence of Dark Matter on the growth of structure and in 1978 he and Martin Rees argued that the properties of galaxies can be understood if they form by gravitationally driven condensation of gas at the centres of extended dark matter halos as these grow steadily in mass through accretion and merging.

His 1983 work with Marc Davis and Carlos Frenk demonstrated that the dark matter could not be made of massive neutrinos, at the time the only known elementary particles which were considered possible candidates.

[6] Their subsequent work together with George Efstathiou was particularly influential in establishing that a universe dominated by Cold Dark Matter (a new kind of elementary particle of unknown type) could produce large-scale structure in the galaxy distribution which does closely resemble that observed.

[9] The Navarro–Frenk–White profile is named after them, and the 1996 and 1997 papers in which they systematically used cosmological N-body simulations to explore its properties are currently White's highest impact theoretical work (with more than 21,000 citations according to Google Scholar).

White's more than 500 publications in the refereed professional literature have been cited more than 281,000 times by other scientists (status end-2024 according to Google Scholar).