Cosmological moduli problem in low cutoff theory

Abstract

We show that the cosmological moduli problem is solved without relying on huge late-time entropy production, if the universal cutoff scale of the theory is a few orders of magnitude smaller than the Planck scale. We obtain a general estimate of the modulus abundance in terms of the inflationary scale and reheating temperature, and find, in particular, that the reheating temperature can be high enough for nonthermal leptogenesis to work.