Large Scale Anomalies in the Microwave Background: Causation and
  Correlation
  Most treatments of large scale anomalies in the microwave sky are a
posteriori, with unquantified look-elsewhere effects. We contrast these with
physical models of specific inhomogeneities in the early universe which then
generate apparent anomalies. Physical models predict correlations between
candidate anomalies, as well as the corresponding signals in polarization and
large scale structure, reducing the impact of cosmic variance. We compute the
apparent spatial curvature associated with large-scale inhomogeneities and show
that it is typically small, allowing for a self-consistent analysis. Focussing
on a single large plane wave inhomogeneity, we show this can contribute to
low-l mode alignment and odd-even asymmetry in the power spectra and the best
fit inhomogeneity accounts for a significant part of the claimed odd-even
asymmetry. We argue that this approach can be generalized to provide a more
quantitative assessment of potential large scale anomalies in the universe.
