Hemispherical Anomaly from Asymmetric Initial States
  We investigate if the hemispherical asymmetry in the CMB is produced from
"asymmetric" excited initial condition. We show that in the limit where the
deviations from the Bunch-Davies vacuum is large and the scale of new physics
is maximally separated from the inflationary Hubble parameter, the primordial
power spectrum is modulated only by position dependent dipole and quadrupole
terms. Requiring the dipole contribution in the power spectrum to account for
the observed power asymmetry, $A=0.07\pm0.022$, we show that the amount of
quadrupole terms is roughly equal to $A^2$. The {\it mean} local bispectrum,
which gets enhanced for the excited initial state, is within the $1\sigma$
bound of Planck 2015 results for a large field model, $f_{\rm NL}\simeq 4.17$,
but is reachable by future CMB experiments. The amplitude of the local
non-gaussianity modulates around this mean value, depending on the angle that
the correlated patches on the 2d CMB surface make with the preferred direction.
The amount of variation minimizes for the configuration in which the short and
long wavelengths modes are around the preferred pole and $|\vec k_3|\approx
|\vec k_{l\approx10}|\ll |\vec k_1|\approx |\vec k_2|\approx |\vec
k_{l\approx2500}|$ with $f_{\rm NL}^{\rm min}\approx 3.64 $. The maximum occurs
when these modes are at the antipode of the preferred pole, $f_{\rm NL}^{\rm
max}\approx 4.81$ . The difference of non-gaussianity between these two
configurations is as large as $\simeq 1.17$ which can be used to distinguish
this scenario from other scenarios that try to explain the observed
hemispherical asymmetry.
