Cosmological screening and the phantom braneworld model
  The scalar and vector cosmological perturbations at all length scales of our
Universe are studied in the framework of the phantom braneworld model. The
model is characterized by the parameter $\Omega_M\equiv M^3/2m^2H_0$, with $M$
and $m$ the 5- and 4-dimensional Planck scales, respectively, and $H_0$ the
Hubble parameter today, while $\Omega_M\rightarrow 0$ recovers the $\Lambda\rm
CDM$ model. Ignoring the backreaction due to the peculiar velocities and also
the bulk cosmological constant, allows the explicit computation of the
gravitational potentials, $\Phi$ and $\Psi$. They exhibit exponentially
decreasing screening behaviour characterized by a screening length which is a
function of the quasidensity parameter $ \Omega_M$.
