I suspect this is a common misconception of the Many Worlds interpretation of quantum mechanics.
I'd like to preface this by paraphrasing Hawking's book A Briefer History of Time: He refers to theories that predict infinites (black holes with infinite density as one example) as inevitably being wrong.
I noticed on the topic of "many worlds" people often interpret the theory as meaning there would be versions of the universe where everything that they could imagine within the realm of physics does happen.
Let's look at an extreme where one person talks about rolling dice and always guessing correctly:
In one of the many worlds dice always roll the number I predicted beforehand. This seems to suggest that in some worlds magic appears to be real.
Another agreed, adding:
In some [of the] many worlds the particles that make me up happen to fly apart while at the exact same time somewhere else radom particles reform a perfect copy of me.
You guys are misinterpreting the concept. There are finite outcomes for any wave function. Let's say in this world in your room you're rolling a die. There are finite ways quantum probability can affect that roll, and it's a very very tiny effect. There could be a world where you get a disease causing tremors that might shake your hand affecting the roll but that doesn't mean the universal wave function where that happens will have you sitting in your room rolling dice right now. Quatum randomness create finite future branches and the real world variation might be incredibly small, except for unusual scenarios, like schrodinger's cat where a tiny quantum wave function has a major real world effect.
Another countered my argument saying under the many worlds interpretation there would be countless previously divergent timelines starting from the big bang. Yet another replied:
Even extremely small probabilities will occur, given infinite tries.
But I think they're wrong about this. My final argument against the idea was this:
Infinite time and space is a mathematical anomaly. Even hawking says something to this effect in his book A Briefer History of Time referring to black holes and any other theoretical concept that predicts infinites. Not that time or space have some fundamental limit, but rather each universe's timeline is limited, the matter within it is limited, and the number of possible particle interactions in feynman diagrams is limited too. If anything the planck length might create a limit on the smallest meaningful positional difference an entity can end up at in a wave function.
But alas, I'm not sure that any one of us in that discussion were anything more than physics enthusiasts. I'd like to know the correct answer from those of you here who can actually speak intelligently on the topic.