## Observational signature of sign of cosmological perturbations?

Kevin J Ludwick
Posts: 4
Joined: April 17 2015
Affiliation: University of Virginia

### Observational signature of sign of cosmological perturbation

Hello,

As far as I know, all observational evidence for cosmological perturbations comes from the CMB power spectrum, which goes like $\delta^2$. Are there any observational signatures that would indicate the sign of $\delta$?

Thanks for any help,
Kevin