  We calculate the exact autocorrelation exponent lambda and persistence
exponent theta, and also amplitudes, in the dilute limit of phase ordering for
dimensions d >= 2. In the Lifshitz-Slyozov-Wagner limit of conserved order
parameter dynamics we find theta = gamma_d*epsilon, a universal constant times
the volume fraction. For autocorrelations, lambda = d at intermediate times,
with a late time crossover to lambda >= d/2 + 2. We also derive lambda and
theta for globally conserved dynamics and relate these to the q->infinity
-state Potts model and soap froths, proposing new poisoning exponents.
