Thermal Unparticles: A New Form of Energy Density in the Universe
| dc.creator | Chen, Shao-Long | |
| dc.creator | He, Xiao-Gang | |
| dc.creator | Hu, Xue-Peng | |
| dc.creator | Liao, Yi | |
| dc.date | 2007-10-26 | |
| dc.date | 2009-01-23 | |
| dc.date.accessioned | 2026-07-07T12:54:58Z | |
| dc.date.available | 2026-07-07T12:54:58Z | |
| dc.description | Unparticle $\U$ with scaling dimension $d_\U$ has peculiar thermal properties due to its unique phase space structure. We find that the equation of state parameter $ω_\U$, the ratio of pressure to energy density, is given by $1/(2d_\U +1)$ providing a new form of energy in our universe. In an expanding universe, the unparticle energy density $ρ_\U(T)$ evolves dramatically differently from that for photons. For $d_\U >1$, even if $ρ_\U(T_D)$ at a high decoupling temperature $T_D$ is very small, it is possible to have a large relic density $ρ_\U(T^0_γ)$ at present photon temperature $T^0_γ$, large enough to play the role of dark matter. We calculate $T_D$ and $ρ_\U(T^0_γ)$ using photon-unparticle interactions for illustration. | |
| dc.description | 5 pages; v3, journal version; | |
| dc.identifier | https://arxiv.org/abs/0710.5129 | |
| dc.identifier | http://arxiv.org/abs/0710.5129 | |
| dc.identifier | Eur.Phys.J.C60:317-321,2009 | |
| dc.identifier | doi:10.1140/epjc/s10052-009-0888-3 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/224120 | |
| dc.subject | High Energy Physics - Phenomenology | |
| dc.subject | Astrophysics | |
| dc.title | Thermal Unparticles: A New Form of Energy Density in the Universe | |
| dc.type | text |