These four squares appear to move at different speeds, stopping and moving, waiting for each other in pairs. In reality, they are always moving at exactly the same constant speed. Seriously. I opened the GIF in Photoshop and used guides to measure it—in every frame, the squares align perfectly.
"Mutliverse" subscribers believe there are other, crazier universes beyond ours that could potentially boast their own unique physics. That's one theory. Another, floated this week, is that the laws of physics in this universe aren't so constant either.