This is probably about the best current measure:nicksauce said:Does anyone have an up-to-date reference for the best value of [itex]\Omega_{\nu}[/itex], given our current understanding of neutrino masses? Dodelson's cosmology book has [itex]\Omega_{\nu}\approx 10^{-3}[/itex], but something more recent would be nice.
The energy density of massive neutrinos refers to the amount of energy contained in a given volume of space due to the presence of massive neutrinos. It is typically measured in units of joules per cubic meter.
The energy density of massive neutrinos can be calculated using the standard formula for energy density, which is mass divided by volume. In this case, the mass is the total mass of all the massive neutrinos present in the volume, and the volume is the size of the region of space being considered.
The energy density of massive neutrinos is significant in cosmology because it contributes to the overall energy budget of the universe. It affects the expansion rate of the universe and can impact the formation and evolution of large-scale structures, such as galaxies and galaxy clusters.
The energy density of massive neutrinos is relatively low compared to other types of matter in the universe, such as dark matter and baryonic matter. However, it is still significant and plays a role in shaping the structure and evolution of the universe.
Yes, the energy density of massive neutrinos can change over time. As the universe expands, the energy density of neutrinos decreases, but it can also be affected by interactions with other particles and the environment. In certain scenarios, the energy density of massive neutrinos may even increase over time.