1997/08/31 by Jiro Hashiba, J. Hashiba, Masahiro Kawasaki +2 · 3 citations
Physics and Astronomy · #Black Holes and Theoretical Physics #Cosmic string #Cosmology and Gravitation Theories #Dilaton #Gravitino #Particle physics #Particle physics theoretical and experimental studies #Physics #Quantum mechanics #String (physics) #Supergravity #Supersymmetry #Supersymmetry breaking #Theoretical physics #Universe #astro-ph #hep-ph
paper · pdf · doi:10.1103/physrevlett.79.4525
published as Phys.Rev.Lett. 79 (1997) 4525-4528 · 13 pages (RevTex file including one figure, use psfig), revised version to be published in Physical Review Letters
arxiv created 1997/10/03 · openalex publication_date 1997/12/08 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The dilaton field in string theories (if it exists) is expected to have a mass of the order of the gravitino mass m3/2 which is in a range of 10^\ensuremath-2keV--1GeV in gauge-mediated supersymmetry breaking models. If this is the case, the cosmic energy density of coherent dilaton oscillation easily exceeds the critical density of the present Universe. We show that even if this problem is solved by a late-time entropy production (thermal inflation) a stringent constraint on the energy density of the dilaton oscillation is derived from experimental upper bounds on the cosmic x( \ensuremathγ)-ray backgrounds. This excludes an interesting mass region, 500keV\ensuremath\lesssimm3/2\ensuremath\lesssim1GeV, in gauge-mediated supersymmetry breaking models.