Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Generating the curvature perturbation without an inflation.
AU - Lyth, David H.
AU - Wands, D.
N1 - This agenda-setting paper proposed a radical modification of the inflationary scenario, whereby the field responsible for the origin of structure in the universe may lie dormant until a rather late epoch. This 'curvaton' mechanism opened the way to new ways of thinking about the early universe. 353 citations (SPIRES). RAE_import_type : Journal article RAE_uoa_type : Physics
PY - 2002/1/3
Y1 - 2002/1/3
N2 - We present a mechanism for the origin of the large-scale curvature perturbation in our Universe by the late decay of a massive scalar field, the curvaton. The curvaton is light during a period of cosmological inflation, when it acquires a perturbation with an almost scale-invariant spectrum. This corresponds initially to an isocurvature density perturbation, which generates the curvature perturbation after inflation when the curvaton density becomes a significant fraction of the total. The isocurvature density perturbation disappears if the curvaton completely decays into thermalised radiation. Any residual isocurvature perturbation is 100% correlated with the curvature. The same mechanism can also generate the curvature perturbation in pre-big bang/ekpyrotic models, provided that the curvaton has a suitable non-canonical kinetic term so as to generate a flat spectrum.
AB - We present a mechanism for the origin of the large-scale curvature perturbation in our Universe by the late decay of a massive scalar field, the curvaton. The curvaton is light during a period of cosmological inflation, when it acquires a perturbation with an almost scale-invariant spectrum. This corresponds initially to an isocurvature density perturbation, which generates the curvature perturbation after inflation when the curvaton density becomes a significant fraction of the total. The isocurvature density perturbation disappears if the curvaton completely decays into thermalised radiation. Any residual isocurvature perturbation is 100% correlated with the curvature. The same mechanism can also generate the curvature perturbation in pre-big bang/ekpyrotic models, provided that the curvaton has a suitable non-canonical kinetic term so as to generate a flat spectrum.
U2 - 10.1016/S0370-2693(01)01366-1
DO - 10.1016/S0370-2693(01)01366-1
M3 - Journal article
VL - 524
SP - 5
EP - 14
JO - Physics Letters B
JF - Physics Letters B
IS - 1-2
ER -