This is called ''dark flow'' which is a named nodded up with two other unexplained astrophysical phenomena[dark matter and dark energy].
The article continues on by saying
The presence of the extra-universal matter suggests that our universe is part of something bigger—a multiverse—and that whatever is out there is very different from the universe we know, according to study leader Alexander Kashlinsky, an astrophysicist at NASA's Goddard Space Flight Center in Maryland.
The theory could rewrite the laws of physics. Current models say the known, or visible, universe—which extends as far as light could have traveled since the big bang—is essentially the same as the rest of space-time (the three dimensions of space plus time).
You can check out the article here. Which was published in national geographic.