Non-Gaussian Correlations Outside the Horizon
Aug, 200824 pages
Published in:
- Phys.Rev.D 78 (2008) 123521
e-Print:
- 0808.2909 [hep-th]
Report number:
- UTTG-06-08
View in:
Citations per year
Abstract: (arXiv)
It is shown that under essentially all conditions, the non-linear classical equations governing gravitation and matter in cosmology have a solution in which far outside the horizon in a suitable gauge the reduced spatial metric (the spatial metric divided by the square of the Robertson--Walker scale factor ) is time-independent, though with an arbitrary dependence on co-moving coordinates, and all perturbations to the other metric components and to all matter variables vanish, to leading order in . The corrections are of order , and are explicitly given for the reduced metric in a multifield model with a general potential. Further, this is the solution that describes the metric and matter produced by single-field inflation. These results justify the use of observed non-Gaussian correlations (or their absence) as a test of theories of single-field inflation, despite our ignorance of the constituents of the universe while fluctuations are outside the horizon after inflation, as long as graphs with loops can be neglected.- 04.60.-m
- 98.80.Jk
- 98.80.-k
- 04.62.+v
- horizon
- correlation: non-Gaussianity
- gravitation
- coupling: matter
- field equations: solution
- field theory: scalar
References(25)
Figures(0)