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The transformation from real space to redshift space is nonlinear; thus, maps in redshift space become increasingly distorted as the redshift $z$ increases. If the deceleration parameter $q_0$ is greater than $-1$, then voids in the distribution of galaxies will be distorted along the line of sight in redshift space. Accurate measurement of the volume and axis ratio of voids, as a function of redshift, will provide an estimate of $q_0$. To test this method of measuring $q_0$, I created a two-dimensional universe free of peculiar velocities, in which galaxies are located near the walls of a Voronoi foam. The area and axis ratios of voids were measured using an algorithm which fits ellipses within voids. In my toy universe, distinguishing between a $q_0 = -1$ universe and a $q_0 = 1/2$ universe requires a survey which goes to a depth of $z \sim 0.1$ in redshift. Peculiar velocities, however, will create an additional source of uncertainty for the values of $q_0$ measured by this method in n-body simulations and in the real universe.
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