 Earman and Norton (1996) follow Allis and Koetsier (and Littlewood and Ross) in demanding that the worldlines of the balls in the jar be continuous, but point out that there is a different sense of discontinuity that develops as a consequence. (A ‘worldline’ is used here to describe the trajectory of a particle through space and time; it is discussed more below in the section on Time in Relativistic Spacetime.) Namely, if one views the number of balls in the jar as approximated by a function \(N(t)\) of time, then this “number function” is discontinuous in the Littlewood-Ross supertask, blowing up to an arbitrarily large value over the course of the supertask before dropping discontinuously to 0 once it is over. In this sense, the Littlewood-Ross paradox presents us with a choice, to either,