Direction dependence of cosmological parameters due to cosmic
  hemispherical asymmetry
  Persistent evidence for a cosmic hemispherical asymmetry in the temperature
field of cosmic microwave background (CMB) as observed by both WMAP as well as
PLANCK increases the possibility of its cosmological origin. Presence of this
signal may lead to different values for the standard model cosmological
parameters in different directions, and that can have significant implications
for other studies where they are used. We investigate the effect of this cosmic
hemispherical asymmetry on cosmological parameters using non-isotropic Gaussian
random simulations injected with both scale dependent and scale independent
modulation strengths. Our analysis shows that $A_s$ and $n_s$ are the most
susceptible parameters to acquire position dependence across the sky for the
kind of isotropy breaking phenomena under study. As expected, we find maximum
variation arises for the case of scale independent modulation of CMB
anisotropies. We find that scale dependent modulation profile as seen in PLANCK
data could lead to only $1.25\sigma$ deviation in $A_s$ in comparison to its
estimate from isotropic CMB sky.
