2004/02/29 by David H. Lyth, David H Lyth, Takeo Moroi · 2 citations
Physics and Astronomy · #Cosmology #Cosmology and Gravitation Theories #Hubble volume #Hubble's law #Inflation (cosmology) #Metric expansion of space #Particle physics theoretical and experimental studies #Quantum and Classical Electrodynamics #Scalar (mathematics) #Scalar field #Slow roll #Universe #hep-ph
paper · pdf · doi:10.1088/1126-6708/2004/05/004
published as JHEP 0405 (2004) 004 · 21 pages, published version
openalex publication_date 2004/05/05 · arxiv created 2004/05/10 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We consider the effective mass-squared in the early Universe, of a scalar field which has only Planck-suppressed couplings with light fields and whose true mass is less than the Hubble parameter H. A detailed investigation shows that the effective mass-squared generically is of order ± H2 during inflation and matter-domination, but much smaller during radiation domination. We consider the special circumstances under which the mass-squared may be much bigger or much smaller than the generic value.