Royal Astronomical Society | 2017 Apr 26
[c][attachment=0]CMB%20Cold%20Spot[1].jpg[/attachment][/c][hr][/hr]A supervoid is unlikely to explain a 'Cold Spot' in the cosmic microwave background, according to the results of a new survey, leaving room for exotic explanations like a collision between universes. ...
The cosmic microwave background (CMB), a relic of the Big Bang, covers the whole sky. At a temperature of 2.73 degrees above absolute zero (or -270.43 degrees Celsius), the CMB has some anomalies, including the Cold Spot. This feature, about 0.00015 degrees colder than its surroundings, was previously claimed to be caused by a huge void, billions of light years across, containing relatively few galaxies.
The accelerating expansion of the universe causes voids to leave subtle redshifts on light as it passes through via the integrated Sachs-Wolfe effect. In the case of the CMB this is observed as cold imprints. It was proposed that a very large foreground void could, in part, imprint the CMB Cold Spot which has been a source of tension in models of standard cosmology. ...
Evidence against a supervoid causing the CMB Cold Spot - Ruari Mackenzie et al
- arXiv.org > astro-ph > arXiv:1704.03814 > 12 Apr 2017
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