Cosmological constraints on large extra dimensions

摘要

We calculate the production of massive Kaluza-Klein (KK) modes via nucleon-nucleon gravi-bremsstrahlung in the early universe. Overproduction of these states would result in early matter domination and, therefore, a low age for the universe so it is possible to place constraints on the number and size of large extra dimensions. The constraints are stronger than those from Sn1987a - for 2 large extra dimensions and T-QCD = 170 MeV, we show the fundamental scale must be larger than 1000 TeV. (C) 2001 Published by Elsevier Science B.V. References: 15