- While the overall constraints are inconclusive, uncorrelated isocurvature cold dark matter modes are found to be unlikely.
- For instance, in 1987, he proposed the primordial isocurvature baryon model for the development of the early universe.
- For isocurvature fluctuations, the density variations for one component do not necessarily correspond to density variations in other components.
- While it is usually assumed that the initial fluctuations are adiabatic, the possibility of isocurvature fluctuations can be considered given current cosmological data.
- Silk damping is not as significant in models of cosmological development which posit early isocurvature fluctuations ( i . e . fluctuations which do not require a constant ratio of baryons and photons ).
- Isocurvature density perturbations produce a series of peaks whose angular scales ( " l " values of the peaks ) are roughly in the ratio 1 : 3 : 5 : . . ., while adiabatic density perturbations produce peaks whose locations are in the ratio 1 : 2 : 3 : . . . Observations are consistent with the primordial density perturbations being entirely adiabatic, providing key support for inflation, and ruling out many models of structure formation involving, for example, cosmic strings.