In physics, chemistry and materials science, percolation (from Lat. percōlāre, to filter or trickle through) concerns the movement and filtering of fluids through porous materials (for more details see percolation theory). During the last five decades, percolation theory, an extensive mathematical model of percolation, has brought new understanding and techniques to a broad range of topics in physics, materials science, complex networks, epidemiology as well as in geography.

Percolation typically exhibits universality. Statistical physics concepts such as scaling theory, renormalization, phase transition, critical phenomena and fractals are useful to characterize percolation properties. Combinatorics is commonly employed to study percolation thresholds. Applications / specific examples include:

By analytical studies, only few exact results can be obtained for percolation. Hence, many results have been obtained from computer simulations. The current fastest algorithm for percolation was published in 2000 by Mark Newman and Robert Ziff.

Béla Bollobás FRS (born August 3, 1943 in Budapest, Hungary) is a Hungarian-born British mathematician who has worked in various areas of mathematics, including functional analysis, combinatorics, graph theory, and percolation.

As a student, he took part in the first three International Mathematical Olympiads, winning two gold medals. He wrote his first doctorate in discrete geometry under the supervision of László Fejes Tóth and Paul Erdős in 1967, after which he spent a year in Moscow with Israïl Moiseevich Gelfand. After spending a year at Oxford University (Christ Church), and vowing never to return to Hungary due to his disillusion with the 1956 Soviet intervention and subsequent puppet communist regime, he went to Cambridge University, where in 1972 he received a Ph.D. in functional analysis under the supervision of Frank Adams.

He has been a Fellow of Trinity College, Cambridge since 1970; in 1996 he was appointed to the Jabie Hardin Chair of Excellence at the University of Memphis, and in 2005 he was awarded a Senior Research Fellowship at Trinity College.