Matrix product state

Okay, imagine you have a bunch of Legos that you want to put together to make a really cool shape. But you don't have enough Legos to build the whole shape at once, so you have to build it piece by piece.

That's kind of like what a matrix product state is. It's a way of building up a really big mathematical shape (called a quantum state) by putting together lots of smaller pieces (called matrices).

Each matrix represents a little piece of the bigger shape, and they all fit together perfectly to create the final result. It's like building a Legos tower, one block at a time, until you have a really tall tower.

But why do people use matrix product states? Well, it turns out that these kinds of shapes are really important in physics, because they can help us understand how really tiny things like atoms and molecules behave. So scientists use matrix product states to study all kinds of interesting phenomena, like superconductivity and magnetism.

So that's what a matrix product state is! It's a way of building up a big mathematical shape from lots of smaller pieces, kind of like building a Legos tower. And scientists use these shapes to understand some really interesting physics.