Probabilities in the Arkani-Hamed-Dimopolous-Kachru landscape

Abstract

In a previous paper we found that in the context of the string theory ``discretuum'' proposed by Bousso and Polchinski, the cosmological constant probability distribution varies wildly. However, the successful anthropic predictions of the cosmological constant depend crucially on the assumption of a flat prior distribution. We conjectured that the staggered character of our Bousso-Polchinski distribution will arise in any landscape model which generates a dense spectrum of low-energy constants from a wide distribution of states in the parameter space of the fundamental theory. Here we calculate the volume distribution for $\Lambda$ in the simpler Arkani-Hamed-Dimopolous-Kachru landscape model, and indeed this conjecture is borne out.