Are we in a simulation? 

Wave-particle duality is a concept in quantum mechanics that suggests objects like electrons and photons can act both as particles and waves. In video games, you can think of it like this:
Imagine you're playing a game where your character can switch between being a solid character that interacts with objects (like opening doors or pushing buttons) and being a ghost that can pass through walls. The "solid character" mode is similar to the particle nature of electrons and photons, where they're like tiny, solid objects. The "ghost" mode is like their wave nature, where they spread out and can go through barriers (in a way, by being everywhere at once within a certain area).
In the quantum world, things like electrons don't choose to be either a particle or a wave; they're both at the same time until we observe them, somewhat like how a game character could switch modes based on player commands, but on a much more fundamental and mysterious level.