# Entanglement isn't just for spin

## TL;DR

This paper broadens the understanding of quantum entanglement by illustrating its occurrence in spatial wave functions beyond spin systems, providing educational tools and insights into quantum mechanics principles.

## Contribution

It introduces pictorial examples of entangled wave functions in spatial variables and discusses their dynamic emergence and quantification methods.

## Key findings

- Entanglement exists in spatial wave functions of multi-degree systems.
- Pictorial representations aid in teaching quantum entanglement.
- Methods to quantify entanglement in spatial wave functions are described.

## Abstract

Quantum entanglement occurs not just in discrete systems such as spins, but also in the spatial wave functions of systems with more than one degree of freedom. It is easy to introduce students to entangled wave functions at an early stage, in any course that discusses wave functions. Doing so not only prepares students to learn about Bell's theorem and quantum information science, but can also provide a deeper understanding of the principles of quantum mechanics and help fight against some common misconceptions. Here I introduce several pictorial examples of entangled wave functions that depend on just two spatial variables. I also show how such wave functions can arise dynamically, and describe how to quantify their entanglement.