1 research outputs found
Angular correlations on causally-coherent inflationary horizons
We develop a model for correlations of cosmic microwave background anisotropy
on the largest angular scales, based on standard causal geometrical
relationships in slow-roll inflation. Unlike standard models based on quantized
field modes, it describes perturbations with nonlocal directional coherence on
spherical boundaries of causal diamonds. Causal constraints reduce the number
of independent degrees of freedom, impose new angular symmetries, and eliminate
cosmic variance for purely angular 2-point correlations. Distortions of causal
structure from vacuum fluctuations are modeled as gravitational memory from
randomly oriented outgoing and incoming gravitational null shocks, with
nonlocally coherent directional displacements on curved surfaces of causal
diamonds formed by standard inflationary horizons. The angular distribution is
determined by axially symmetric shock displacements on circular intersections
of the comoving sphere that represents the CMB photosphere with other
inflationary horizons. Displacements on thin spheres at the end of inflation
have a unique angular power spectrum that approximates the standard
expectation on small angular scales, but differs substantially at large angular
scales due to horizon curvature. For a thin sphere, the model predicts a
universal angular correlation function with an exact ``causal
shadow'' symmetry, , and significant large-angle
parity violation. We apply a rank statistic to compare models with WMAP and
Planck satellite data, and find that a causally-coherent model with no shape
parameters or cosmic variance agrees with the measured better than
a large fraction () of standard model realizations. Model-independent
tests of holographic causal symmetries are proposed