Remember these fuzzy, familial grizzlies from your childhood?

They're the "The Berenstain Bears," stars of the book series of the same name created by married couple Stan and Jan Berenstain in the 1960s. You'll likely recall their smiling faces from your school library or a book fair (there are literally hundreds of books), but you might not remember their name. Or if you do, you may remember it as Berenstein with an "e," not Berestain with an "a." And you're not alone.

An emerging number of vocal "-stein" proponents have popped up online over the past few years, all seemingly branching out from this Blogspot post, or maybe this Reddit post (or this one or this one). This story has been around for a while, deposited in the most mindf--k-centric corners of the Internet.

But for the past week, rapper/producer El-P of Run The Jewels fame has been pushing it into the mainstream. El tweeted out a reference to the discrepancy on Aug. 4...

...then spent the next few days probing deeply into it, ultimately giving some face time to the bigger issue here: the theory that #BerenstainRift is proof that alternate universes exist.

The gist of the theory is that there's an original timeline in which the bears have always been called Berenstein, but at some point, we deviated from that and are now living in an alternate reality -- pretty much exactly what happens in the last third of "Back To The Future 2." In this parallel universe, the bears are now called (and have always been called) Berenstain.

Is this even possible? How can so many people remember something that's simply not true? For the answer, we headed into the realm of theoretical quantum physics to talk to Dr. Howard Wiseman, a professor at Griffith University in Australia. He's not particularly sold on the idea that #BerenstainRift is evidence enough of alternate universes (though he found the theory "amusing").

"As spooky as it seems, I believe, as a scientist, that it is far easier to explain through psychology

(memory is fallible) than through people slipping between parallel universes," Wiseman wrote in an email to MTV News.

His published work has included an argument that parallel universes exist and may actually interact with each other -- but only, he said, among universes that are close together.

"You might think that changing an 'e' to an 'a' is not a big change, but when we say 'close' we mean really indistinguishable on a macroscopic scale, only different at the microscopic, quantum-scale, level," he wrote. "In any case, I don't see anything in our theory, or any physics theory of parallel universes, that would lead to the effect where huge numbers of (but not all) people end up in a universe where their memories disagree with reality."

Wiseman concluded by saying if #BerenstainRift is real, it's a "supernatural phenomenon" that science merely can't explain.

So, what would El-P say to the folks who simply can't wrap their heads around it?

Honestly, same. I'm one of them.