2015/04/08 by Peter W. Graham, Jeremy Mardon, Surjeet Rajendran
Physics and Astronomy · #Astrophysics #Cosmic microwave background #Cosmology and Gravitation Theories #Dark Matter and Cosmic Phenomena #Dark matter #Inflation (cosmology) #Inflaton #Particle physics #Particle physics theoretical and experimental studies #Physics #Quantum #Quantum fluctuation #Quantum mechanics #Theoretical physics #hep-ph #hep-th
paper · pdf · doi:10.1103/physrevd.93.103520
published as Phys. Rev. D 93, 103520 (2016) · 32 pages, 6 figures
arxiv created 2015/04/08 · openalex publication_date 2016/05/18 · arxiv updated 2016/05/25 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We calculate the production of a massive vector boson by quantum fluctuations during inflation. This gives a novel dark-matter production mechanism quite distinct from misalignment or thermal production. While scalars and tensors are typically produced with a nearly scale-invariant spectrum, surprisingly the vector is produced with a power spectrum peaked at intermediate wavelengths. Thus dangerous, long-wavelength, isocurvature perturbations are suppressed. Further, at long wavelengths the vector inherits the usual adiabatic, nearly scale-invariant perturbations of the inflaton, allowing it to be a good dark-matter candidate. The final abundance can be calculated precisely from the mass and the Hubble scale of inflation, HI. Saturating the dark-matter abundance we find a prediction for the mass m\ensuremath≈10^\ensuremath-5 eV\ifmmode×\else\texttimes\fi\phantom\rule0ex0ex(1014 GeV/HI)4. High-scale inflation, potentially observable in the cosmic microwave background, motivates an exciting mass range for recently proposed direct-detection experiments for hidden photon dark matter. Such experiments may be able to reconstruct the distinctive, peaked power spectrum, verifying that the dark matter was produced by quantum fluctuations during inflation and providing a direct measurement of the scale of inflation. Thus a detection would not only be the discovery of dark matter, it would also provide an unexpected probe of inflation itself.