Dark matter and dark radiation in brane world cosmology and its observational test in the BBN, CMB and supernovae

A massive cold dark matter particle is likely to disappear when it is quantized in a Randall-Sundrum noncompact higher dimensional AdS5 spacetime. To distinguish disappearance of our dark matter particle from the previous decaying particles, we refer to it as disappearing cold dark matter (DCDM). We look for cosmological evidence for this new paradigm and show that this new model is consistent with all data at the 95% C.L., satisfying all sorts of presently available observational constraints from the redshift-luminosity relation of Type Ia supernovae, the mass-to-light ratios of galaxy clusters, and the power spectrum of cosmic microwave background [Phys. Rev. D 68 (2003) 083518].