A svedberg (symbol S, sometimes Sv, not to be confused with Sv for the SI unit sievert as well as the non-SI sverdrup) is a non-SI physical unit used to characterize the behaviour of a particle type in ultracentrifugation. Bigger particles have higher svedberg values. It is a unit of time amounting to 10-13 s or 100 fs. It is named after the Swedish chemist Theodor Svedberg (1884-1971), winner of the Nobel prize in chemistry in 1926 for his work in the chemistry of colloids and his invention of… (More on Svedberg)