(Image from ESA and Durham University via http://www.astronomy.com)
A Cold Spot is a region of our Universe that when measured by background radiation it is significantly colder to other surrounding areas within the Cosmos. The mainstay theory for this “Cold Spot” is the presence of a Super-void, a massive region of the Universe that holds fewer Galaxies. The common theory, which has been recently challenged, is that these Voids are in an aliment to a CMB cold spot, which in-turn decreases the energy of cosmic microwave background (CMB) photons, known in physics as the Integrated Sachs-Wolfe effect – thus causing a region of the Universe to be colder than other cosmic structures. Measurement and calculations from Ruari Mackenzi and Professor Tom Shanks at Durham University’s Center for Extragalactic Astronomy believe that a Super-void is not the reason that a colder region of Space exists. In their recent paper they hypothesize through analyzing Super-void data, that any ‘unlikely’ fluctuation devoid of the standard model of the Big Bang, may lead to an exotic explanation for this abnormality. Which brings the Parallel Universe theory into play.
Even without a supervoid in the way, the team estimates a likelihood that the Cold Spot appeared by random chance as 1 in 50. According to Shanks, “This means we can’t entirely rule out that the Spot is caused by an unlikely fluctuation explained by the standard model. But if that isn’t the answer, then there are more exotic explanations.”
Such exotic explanations, he says, include “a collision between our universe and another bubble universe. If further, more detailed, analysis of CMB data proves this to be the case then the Cold Spot might be taken as the first evidence for the multiverse – and billions of other universes may exist like our own.”
The multiverse describes a set of infinite universes, which includes the one in which we live. To date, no evidence has been found that the multiverse is more than science fiction, but researchers are continually pushing the boundaries of the observable universe to determine whether this concept is fact or fiction. While at the moment the Cold Spot is certainly not definitive evidence of a multiverse, it does indicate a problem in our standard cosmological model that may need addressing if the cause of the temperature fluctuation in this area remains unclear
These topic of Voids and Parallel Universes were discussed in my last book Cataclysmal.