TY - JOUR

T1 - A general proof of the conservation of the curvature perturbation.

AU - Lyth, David H.

AU - Malik, Karim A.

AU - Sasaki, Misao

N1 - This pioneering paper showed that the so-called delta N formalism can be radically generalised, to provide a powerful tool for calculating the non-gaussianity of the primordial perturbation. It has already been used as the starting point for new directions of research by several groups. 78 citations (SPIRES). RAE_import_type : Journal article RAE_uoa_type : Physics

PY - 2005/5/10

Y1 - 2005/5/10

N2 - Without invoking a perturbative expansion, we define the cosmological curvature perturbation, and consider its behaviour assuming that the universe is smooth over a sufficiently large comoving scale. The equations are simple, resembling closely the first-order equations, and they lead to results which generalize those already proven in linear perturbation theory and (in part) in second-order perturbation theory. In particular, the curvature perturbation is conserved provided that the pressure is a unique function of the energy density.

AB - Without invoking a perturbative expansion, we define the cosmological curvature perturbation, and consider its behaviour assuming that the universe is smooth over a sufficiently large comoving scale. The equations are simple, resembling closely the first-order equations, and they lead to results which generalize those already proven in linear perturbation theory and (in part) in second-order perturbation theory. In particular, the curvature perturbation is conserved provided that the pressure is a unique function of the energy density.

KW - cosmological perturbation theory

KW - inflation

KW - physics of the early universe

U2 - 10.1088/1475-7516/2005/05/004

DO - 10.1088/1475-7516/2005/05/004

M3 - Journal article

VL - 0505

SP - 004

JO - Journal of Cosmology and Astroparticle Physics

JF - Journal of Cosmology and Astroparticle Physics

SN - 1475-7516

ER -