Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Signature of Patchy Reionization in the Polarization Anisotropy of
  the CMB   The inhomogeneous ionization state of the universe when the first sources of
ionizing radiation appeared should lead to anisotropies in the polarization of
the cosmic microwave background. We use cosmological simulations of the process
by which the first sources ionized the intergalactic medium to study the
induced polarization anisotropies. We find that the polarization anisotropies
have rms of order ~0.01 \mu K, and local peak values of ~0.1 \mu K, smaller
than those due to gravitational lensing on small scales. The polarization
direction is highly coherent over degree scales. This directional coherence is
not expected from either primary anisotropy or gravitational lensing effects,
making the largest signals due to inhomogeneous ionization relatively easy to
isolate, should experiments achieve the necessary very low noise levels.

13
The categories of this paper are: quant-ph
24
The categories of this paper are: dg-ga
2
The categories of this paper are: math
27
The categories of this paper are: comp-gas
35
The categories of this paper are: mtrl-th
32
The categories of this paper are: atom-ph
11
The categories of this paper are: hep-lat
7
The categories of this paper are: hep-th
25
The categories of this paper are: patt-sol
31
The categories of this paper are: ao-sci
37
The categories of this paper are: supr-con
29
The categories of this paper are: funct-an
18
The categories of this paper are: econ
1
The categories of this paper are: cs
4
The categories of this paper are: cond-mat
21
The categories of this paper are: adap-org