The strangely cold spot in space that was thought to be a “supervoid” could be something you’ve only ever seen in sci-fi movies—but is it science or fiction?
The afterbirth of the universe, or all the radiation left over after it formed, is the cosmic microwave background (CMB). It is basically a snapshot of the early universe when it was only several hundred thousand years old. What made this cold spot stand out on CMB maps was its abnormally high deviation from the relatively consistent temperature of 3,000 degrees Kelvin, which is usually unheard of in any area over one degree across. This one measures five times that. Scientists used to believe it was a “supervoid” that allowed light to pass through, but that was recently disproved because there just isn’t enough of a void in galaxy distribution in the CMB to uphold it.
The collapse of the “supervoid” theory for this bizarre temperature deviation has opened a portal into some exotic theorizing that wouldn’t be out of place on Doctor Who.
Parallel universe, or multiverse, theories are essentially the mutant spawn of string theory, inflation and quantum mechanics. They are also a source of endless controversy among physicists. What some see as a potentially seismic shift in how we view all of time and space is no more real than the TARDIS to others. If quantum mechanics is to be believed, any particle can exist in “superposition,” meaning that same particle could be in several states or places at once. Here is where it gets suspicious. While such a thing has actually been observed at a subatomic level, the electron that supposedly ended up in two places at once only pulled its magic act when researchers’ backs were turned. It reverted to just one destination as soon as a human eyeball was on it.
You could assume that every conceivable possibility of what that electron actually did just existed in its own universe and you simply didn’t have enough eyeballs to see every one. If science prevailed above fiction here, it could mean that the cold spot is actually a scar from a collision with a parallel universe. Scientists who haven’t been watching too much TV say it’s fiction.
The universe is just too vast to assume that if there were infinite parallel universes, we are observing proof of one of them in what is an extremely small piece of sky. So if it isn’t hard evidence for a multiverse, then where did this cold spot come from? The early universe may have just had an irregularity in temperature (albeit an unusually large one). Fluctuations in mass density that influenced temperature fluctuations in the CMB could have influenced its formation. There is also an off chance it could have happened randomly. Or we might just have to rethink everything we know about how temperature inconsistencies happen in deep space.
While quantum physics hasn’t brought any multiverses to light yet, these theories certainly have inspired some awesome science fiction.