# A search for concentric circles in the 7-year WMAP temperature sky maps

@inproceedings{Wehus2010ASF, title={A search for concentric circles in the 7-year WMAP temperature sky maps}, author={Ingunn Kathrine Wehus and Hans Kristian Eriksen}, year={2010} }

In a recent analysis of the 7-year WMAP temperature sky maps, Gurzadyan and Penrose claim to find evidence for violent pre-Big Bang activity in the form of concentric low-variance circles at high statistical significance. In this paper, we perform an independent search for such concentric lowvariance circles, employing both χ statistics and matched filters, and compare the results obtained from the 7-year WMAP temperature sky maps with those obtained from ΛCDM simulations. Our main findings are…

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