The von Neumann-Wigner interpretation is a way of understanding how we measure things in quantum physics. It's basically like playing a game where you can never know everything for sure, but you can be pretty good at guessing what is going to happen.
Imagine you're playing a game of hide and seek with your friends, but instead of finding them in a specific spot, you have to guess where they are based on clues. You might hear them giggling from one direction, or catch a glimpse of their shoe from another. You can never be certain where they are, but you can make educated guesses based on the clues you have.
In quantum physics, it's similar. We can never know everything about an object, like its exact location and speed. Instead, we have to use probabilities to make educated guesses about what will happen when we try to measure it.
The von Neumann-Wigner interpretation suggests that these measurements actually create reality. It's like when you peek under the bed and suddenly there's a monster there – except instead of a monster, you're actually making the object be in a certain place and have a certain speed.
So just like in the game of hide and seek, we use clues to make our best guess about what will happen when we measure a quantum object. And once we make that measurement, we create the reality we observe.