  In the spherically symmetric case the Einstein field equations take on their
simplest form for a matter-density rho = 1 / (8 pi r^2), from which a radial
metric coefficient g_{rr} \propto r follows. The boundary of an object with
such an interior matter-density is situated slightly outside of its
gravitational radius. Its surface-redshift scales with z \propto \sqrt{r}, so
that any such large object is practically indistinguishable from a black hole,
as seen from exterior space-time. The interior matter has a well defined
temperature, T \propto 1 / \sqrt{r}. Under the assumption, that the interior
matter can be described as an ultra-relativistic gas, the object's total
entropy and its temperature at infinity can be calculated by microscopic
statistical thermodynamics. They are equal to the Hawking result up to a
possibly different constant factor. The simplest solution of the field
equations with rho = 1 / (8 pi r^2) is the so called holographic solution,
short "holostar". It has an interior string equation of state. The strings are
densely packed, explaining why the solution does not collapse to a singularity.
The holographic solution has been shown to be a very accurate model for the
universe as we see it today in Ref[7]. The factor relating the holostar's
temperature at infinity to the Hawking temperature can be expressed in terms
the holostar's interior (local) radiation temperature and its (local)
matter-density, allowing an experimental verification of the Hawking
temperature law. Using the recent experimental data for the CMBR-temperature
and the total matter-density in the universe measured by WMAP, the Hawking
formula is verified to an accuracy of 1%.
