Eigenstates

Eigenstates are like special outfits that objects wear when they are in a certain mood or state of being. Imagine that atoms are like dolls, and they can change their clothes very quickly and easily. Each outfit, or eigenstate, makes the doll look and act a certain way.

Now, let's say we want to study how the atoms in a material are behaving. We can shine light on the material and see what colors are absorbed or reflected. Each color we see corresponds to the doll changing into a different eigenstate outfit. By looking at which colors are absorbed or reflected, we can learn about what eigenstates the atoms are in and how they are interacting with each other.

So, to summarize, eigenstates are like outfits that atoms wear, and we can learn about these outfits by studying how light interacts with a material.