|WMAP cold spot|
The Eridanus Supervoid is the largest supervoid (an area of the universe devoid of galaxies) discovered as of 2007. At a diameter of about one billion light years it is much larger than any other known void and represents a challenge for current theories of the origins of the universe to explain.
It was discovered by linking a "cold spot" in the cosmic microwave background to an absence of radio galaxies in data of the United States National Radio Astronomy Observatory's Very Large Array Sky Survey. There is some speculation that the void may be due to quantum entanglement between our universe and another.
Typically, the largest fluctuations of the primordial CMB temperature occur on angular scales of about 1°. Thus a cold region as large as the "cold spot" appears very unlikely, given generally accepted theoretical models.
Various alternative explanations exist, including a so-called Eridanus Supervoid or Great Void. This would be an extremely large region of the universe, roughly 150 Mpc or 500 million light-years across, at redshift , containing a density of matter much smaller than the average density at that redshift. Such a void would affect the observed CMB via the integrated Sachs-Wolfe effect.
If a comparable supervoid did exist, it would be one of the largest structures in the observable Universe.
If you are following me this blog on Space Theology we have just concluded a wonderful tour to the limits of the observable Universe with the help of the Hayden Planetarium Digital Universe Atlas. Brian Abbott explains in the Guide Cosmic Microwave Background Radiation and we can admire in Partiview a 3D model of the WMAP data.
And now, right away after that, we hit the possibility of the existence of Multiverse as an explanation to an enormous "cold spot" noted the direction of the Eridanus (River Po) constellation. Some have explained this void of anything as a quantum entanglement between our universe and another.
Our trip to space exploration is getting more and more grandiose!