0 0.4 0.8 1.2 1.6 0.4 0.8 1.2 1.6 maximum-current  phase low-density phase high-density phase FIG. 9: Phase diagram of the TASEP on the lattice (dotted lines) and in continuous- space (solid lines) for L=500. The grey triangle denotes a region in which we are unable to determine the phase boundaries precisely. hand are not sufficient to verify this. The phase boundaries for L = 100 and L = 200 are nearly the same as for L = 500, suggesting that the latter are already quite close to limiting (infinite- L ) values. Table I gives the α and β values for the continuous transition lines for the three sizes. There is little sign of systematic variation with system size, other than a small ( ∼ 2 . 5%) increase in β$_{c}$ on going from L = 200 to L = 500. While the continuous-space phase diagram is isomorphic to that of the lattice model, there are some differences between the two cases that appear likely to persist in the infinite-size limit. Since the lattice model possesses particle-hole symmetry, the phase diagram is invariant under the exchange of α and β . Thus the boundary between the high- and low-density phases is a straight line extending from the origin to the point (1 / 2 , 1 / 2) in the α - β plane. The phase diagram of the continuous-space model does not possess this symmetry; the phase boundary between the high- and 17