Blue and violet graviton spectra from a dynamical refractive index
We show that the spectral energy distribution of relic gravitons mildly increases for frequencies smaller than the μHz and then flattens out whenever the refractive index of the tensor modes is dynamical during a quasi-de Sitter stage of expansion. For a conventional thermal history the high-frequen...
| Main Author: | |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Elsevier
2019-02-01
|
| Series: | Physics Letters B |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S037026931930005X |