The multiverse is one of the most intriguing theories around, only it's one that has yet to be proven. The theory is that there are an infinite number of universes and ours is only a version of reality; the rest are in a dimension humans can't access (yet).

A new study has offered the best evidence so far of the existence of these parallel universes. According to a report from The Guardian, researchers recently analyzed what's called the "cold spot" that was spotted in the radiation from the formation of the universe over 13 billion years ago.

Blanketing the entire sky is the cosmic microwave background (CMB), which is a relic of the Big Bang that astronomers can observe for a peek at the early stages of the universe, a report from WIRED said. It has a temperature of 2.73 degrees above absolute zero, but there are certain anomalies like the cold spot that extends 1.8 billion light-years across and 0.00015 degrees colder than its surroundings.

The source of the cold spot, first detected in 2004 and again in 2013, is a mystery. Researchers say that it's not likely to have been produced during the birth of the universe, since the best current theory of its formation -- inflation -- would be mathematically challenging to explain otherwise. Meanwhile, the latest study disproves that the cold spot is just an optical illusion.

While it's still possible that it's merely a fluctuation caused by the standard theory of Big Bang, Durham University's Professor Tom Shanks said that there are more "exotic explanations" for the cold spot's existence.

"Perhaps the most exciting of these is that the Cold Spot was caused by a collision between our universe and another bubble universe," Shanks explained to the Royal Astronomical Society. "If further, more detailed, analysis ... proves this to be the case then the Cold Spot might be taken as the first evidence for the multiverse."

The study was published in the journal Monthly Notices of the Royal Astronomical Society.