A new theory suggests that there may be a bizarre universe, or “anti-universe,” that has running back-ward in time since before the Big Bang.
The wild theory suggests that as early universe was small, hot & dense, it was uniform enough that time looked symmetric going back-ward & forward, says a report from LiveScience.
Universe running backward
If the new theory were true, it would suggest that dark matter is simply a new type of neutrino particle and that there was no “inflationary period” that caused the early Universe to expand rapidly. The team behind the theory say that future experiments studying gravitational waves or neutrinos could help to un-cover the existence of this mirror anti-Universe.
The theory is based on the CPT symmetry law which states that charge, parity and time are symmetric and you will see the same response when they are flipped. Sometimes there are violations of this rule, but physicists have never observed a violation of charge, parity & time at the same time.
In their new paper, published in journal Annals of Physics, the team behind the new theory proposed extending this combined symmetry beyond the Big Bang. If we apply the CPT symmetry law to the entire universe, there must be a mirrored image cosmos that balance-out our entire existence. This anti-universe would have all the opposite charges to ours own & would go back in time, the researchers theorize.
Can we observe anti universe?
Researchers say a CPT symmetric universe would naturally fill-out with particles due to its opposite symmetric partner, meaning there would be no need for inflation theory to explain the universe’s rapid expansion of very early universe.
The theory could also explain why physicists have never observed “right handed” neutrinos – they have only observed 3 types of neutrinos, the electro neutrino, the muon neutrino & the tau neutrino, all of which spin to the left relative to their motion.
A CPT-compliant universe would require the existence of at least one type of right-handed neutrino that would be largely invisible to physics experiments and only affect the rest of the universe through gravity. The researchers also point out that such a particle provides an explanation for dark matter, since anti-universe conditions would fill our universe with enough right-handed neutrinos to account for mysterious force.
All of this might sound like it was inspired by the Marvel Cinematic Universe’s recent forays into multiverse-focused narratives, but the researchers say there are several factors that might lend credence to their theory. We could never access this so-called anti-universe as it technically occurs before our own big bang. For example, his theory states that inflation never happened. So if the next set of experiments looking for early-period gravitational waves caused by that inflation come-up empty, it would be a strong indication that the CPT anti-universe theory may be correct.