2018/07/31 by Diego Cruces, Cristiano Germani, Tomislav Prokopec · 66 citations
Economics, Econometrics and Finance · Physics and Astronomy · #Cosmological perturbation theory #Cosmology #Cosmology and Gravitation Theories #Formalism (music) #Inflation (cosmology) #Relativity and Gravitational Theory #Stochastic process #Stochastic processes and financial applications #Zeroth law of thermodynamics #astro-ph.CO #gr-qc #hep-ph #hep-th
paper · pdf · doi:10.1088/1475-7516/2019/03/048
published in Journal of Cosmology and Astroparticle Physics 2019(03), 048 (Institute of Physics) · v3: typo in the appendix corrected. Results unchanged. Published version in JCAP
openalex created_date 2019/03/22 · openalex publication_date 2019/03/29 · arxiv created 2019/04/01 · arxiv updated 2019/04/10 · openalex updated_date 2026/08/05
After giving a pedagogical review we clarify that the stochastic approach to inflation is generically reliable only at zeroth order in the (geometrical) slow-roll parameter 1 if and only if 2 2 ≪ 6/ 1 , with the notable exception of slow-roll. This is due to the failure of the stochastic Δ N formalism in its standard formulation. However, by keeping the formalism in its regime of validity, we showed that, in ultra-slow-roll, the stochastic approach to inflation reproduces the power spectrum calculated from the linear theory approach.