  Supernova Ia redshifts are fitted with a simple $5D$ model: the galaxies are
assumed to be enclosed in a giant $S^3$-spherical shell of significant
thickness, which expands (ultra)relativisticaly in Minkowski (1+4)$D$-space.
This model, as compared with the kinematic (1+3)$D$ Milne cosmological model
(which was reinvented by Prof Farley), goes in line with the Copernican
principle: any galaxy observes the same isotropic distribution of distant
galaxies and supernovae, as well as the same Hubble plot of SN Ia distance
modulus $\mu$ vs redshift $z$. A good fit is obtained (no free parameters); it
coincides with the Milne model (empty model) at low $z$, while shows some more
luminosity at high $z$, leading to 1% decrease in the true distance modulus
(and 50% increase in luminosity) at $z\sim2$.
  The model proposed can be also interpreted as a sort of FLRW-model with the
scale factor $a(t)=t/t_0$; this could hardly be a solution of general
relativity (without inventing some super-dark energy with $w=-1/3$, a sort of
dark curvature); 5$D$ GR is also unsuitable -- it has no longitudinal
polarization. However, there still exists the other theory (with $D=5$ and no
singularities in solutions), the other game in the town, which seems to be able
to do the job.
