CMB lensing and the WMAP cold spot

Abstract

Cosmologists have suggested a number of intriguing hypotheses for the origin of the ``WMAP cold spot,'' the coldest extended region seen in the cosmic microwave background (CMB) sky, including a very large void and a collapsing texture. Either hypothesis predicts a distinctive CMB lensing signal. We show that the upcoming generation of high resolution CMB experiments such as Atacama Cosmology Telescope and the South Pole Telescope should be able to detect the signatures of either textures or large voids. If either signal is detected, it will have profound implications for cosmology.