How hot are expanding universes ?
| dc.creator | Obadia, Nathaniel | |
| dc.date | 2008-04-17 | |
| dc.date | 2008-10-16 | |
| dc.date.accessioned | 2026-07-07T11:49:57Z | |
| dc.date.available | 2026-07-07T11:49:57Z | |
| dc.description | A way to address the conundrum of Quantum Gravity is to illustrate the potentially fundamental interplay between quantum field theory, curved space-times physics and thermodynamics. So far, when studying moving quantum systems in the vacuum, the only known perfectly thermal temperatures are those obtained for constant (or null) accelerations $A$ in constant (or null) Hubble parameters $H$ space-times. In this Letter, restricting ourselves to conformally coupled scalar fields, we present the most comprehensive expression for the temperature undergone by a moving observer in the vacuum, valid for any time-dependent linear accelerations and Hubble parameters: $T=\sqrt{A^2 + H^2 + 2 \dot H\dot t}/{2π}$ where $\dot t=\d t/\d\t$ is the motion's Lorentz factor. The inequivalence between a constant $T$ and actual thermality is explained. As a byproduct, all the Friedman universes for which observers at rest feel the vacuum as a thermal bath are listed. | |
| dc.description | 4 pages, no figure, version accepted in PRD | |
| dc.identifier | https://arxiv.org/abs/0804.2890 | |
| dc.identifier | http://arxiv.org/abs/0804.2890 | |
| dc.identifier | Phys.Rev.D78:083532,2008 | |
| dc.identifier | doi:10.1103/PhysRevD.78.083532 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/203419 | |
| dc.subject | General Relativity and Quantum Cosmology | |
| dc.subject | High Energy Physics - Theory | |
| dc.title | How hot are expanding universes ? | |
| dc.type | text |