Our universe is a very puzzling place. The more we explore it with our limited technology, the more we realize how much we still have to learn.
Despite this, in recent years we have made great progress in understanding our cosmos. And along the way, we’ve encountered several mysteries that may force us to rethink everything we thought was possible.
There is a massive region of nothingness in the universe. The relict cold spot or the Eridanus Supervoid is an area in the constellation Eridanus with unusually low microwave radiation and a large size compared to the expected properties of the cosmic microwave background radiation.
This region of “nothingness” spans 1.8 billion years across and is about 3 billion light-years from our galaxy.
But it is not only large, but also incredibly cold, unlike the areas around it. The cold spot is about 70 µK (0.00007 K) colder than the average CMB temperature (about 2.7 K). Standard cosmology cannot explain such a giant cosmic hole.
Scientists believe the discovery of this massive sphere of nothingness could explain long-standing cosmological mysteries.
Some scientists believe that this “cold spot” in space may be evidence of the existence of parallel universes. Moreover, some dare to say that there could be billions of universes just like ours.
So far, the most popular explanation has been that the mysterious cold spot is the result of a super-void. Space voids are vast spaces between filaments (the largest structures in the universe) that contain very few or no galaxies. Thus, this massive region of nothingness has been named the Eridanian super-void.
Some scientists suggest that this cosmic mystery may be the first ever evidence of a multiverse and Eridani’s super-void may be the result of a collision between two universes. So our universe may be just one of billions of other universes.
To understand the mysterious supervoid, we look at the cosmic microwave background, which scientists commonly refer to as the CMB. The cosmic microwave background is a kind of map of the radiation left over from the Big Bang.
This strange cosmic radiation was emitted shortly after the Big Bang, several hundred thousand years after it.
The CMB provides scientists with the earliest insight into our nascent universe and has become one of the most important components in the study of the universe in which we live.
The cold spot, also known as the Eridani Super Void, was discovered by astronomers in 2004 using data recorded by the Wilkinson Microwave Anisotropy Probe (WMAP).
Scientists have long been trying to explain the origin of this mysterious cold spot. Progress in its understanding was made in 2015, when scientists got closer to the solution, as research showed that this is a real “Superoid”, where the density of galaxies is much lower than in the rest of the universe.
But, oddly enough, other studies have not been able to replicate this result.
Then a study of more than 7,000 galaxies showed that the mysterious cold spot in the cosmic microwave background (CMB) is not caused by a giant void in space, potentially opening the door to more exotic explanations.
According to Laura Mersini-Houghton, cosmologist, theoretical physicist and professor at the University of North Carolina at Chapel Hill, the mysterious cold spot in the universe is most likely the fingerprint of another universe outside of our own, caused by quantum entanglement between universes before they were separated by cosmic inflation.
Laura Mersini-Houghton said: “Standard cosmology can’t explain such a gigantic cosmic hole” and advanced the remarkable hypothesis that the this cold spot is “… an unmistakable imprint of another universe beyond the edge of our own.”
If this is true, then this is the first empirical evidence for the existence of a parallel universe (although theoretical models of parallel universes have existed before).
That mysterious process of inflation and the Big Bang have convinced some researchers that multiple universes are possible, or even very likely. According to theoretical physicist Alexander Vilenkin of Tufts University in Massachusetts, inflation didn’t end everywhere at the same time. While it ended for everything that we can detect from Earth 13.8 billion years ago, cosmic inflation in fact continues in other places.
This is called the theory of eternal inflation. And as inflation ends in a particular place, a new bubble universe forms, Vilenkin wrote for Scientific American in 2011.
Parallel universes are no longer just a feature of a good sci-fi story. There are now some scientific theories that support the idea of parallel universes beyond our own. However, the multiverse theory remains one of the most controversial theories in science.
