| Popis: |
Graviton production due to collapsing extra dimensions is studied. The momenta lying in the extra dimensions are taken into account. A D-dimensional background is matched to an effectively four-dimensional standard radiation-dominated universe. Using observational constraints on the present gravitational wave spectrum, a bound on the maximal temperature at the beginning of the radiation era is derived. This expression depends on the number of extra dimensions, as well as on the D-dimensional Planck mass. Furthermore, it is found that the extra dimensions have to be large. © 2002 The American Physical Society. |
