The Flux of Potentialities was a core concept in Osiran temporal theory, referring to the quantum multi-potentialities of time which made up the multiverse. (COMIC: Spiral Staircase) This flux was also acknowledged in Time Lord temporal theory as the opposite of a fixed point in time, being what the majority of history was composed of. (COMIC: Vortex Butterflies)
The Tenth Doctor naturally sensed the Flux of Potentialities around every moment, navigating possible outcomes to live in a version of history he preferred. (COMIC: Spiral Staircase, Vortex Butterflies) The Tenth Doctor once referred to infinite temporal flux. (TV: The Shakespeare Code)
As a quantum harvester, Dorothy Bell could see across the Flux of Potentialities and manifest potentialities from other versions of possibility. (COMIC: Spiral Staircase, Old Girl)
The Vortex Butterfly and Time Sentinel both acknowledged that complex time travel made time even more complicated than just fixed points and flux, (COMIC: Vortex Butterflies, The Good Companion) with there also existing the fluidity and flow of the Ocean of Time. (COMIC: Vortex Butterflies)