Isocurvature Constraints and Gravitational Ward Identity
arXiv:1302.7078
Abstract
Axions and WIMPZILLAs are well-motivated dark matter candidates with interesting cos- mological implications, such as isocurvature perturbations and non-Gaussianities. How- ever, these predicted implications in the literature are based on the assumption that the cross-correlation between curvature and CDM isocurvature is negligible. This contribution discusses the cross-correlation in the axion and the WIMPZILLA scenarios. Particularly, it is shown that the gravitational Ward identity associated with diffeomorphism invariance plays an important role in this cross-correlation calculation confirming the assumption.
Contributed to the 8th Patras Workshop on Axions, WIMPs and WISPs, Chicago, July 18-22, 2012