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21-cm lensing and the cold spot in the cosmic microwave background
Ely D Kovetz1, Marc Kamionkowski
1Theory Group, Department of Physics and Texas Cosmology Center, The University of Texas, Austin, Texas 78712, USA.
Abstract:
An extremely large void and a cosmic texture are two possible explanations for the cold spot seen in the cosmic microwave background. We investigate how well these two hypotheses can be tested with weak lensing of 21-cm fluctuations from the epoch of reionization measured with the Square Kilometer Array. While the void explanation for the cold spot can be tested with Square Kilometer Array, given enough observation time, the texture scenario requires significantly prolonged observations, at the highest frequencies that correspond to the epoch of reionization, over the field of view containing the cold spot.
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