ELI5: Explain Like I'm 5

Topologies on the set of operators on a Hilbert space

Imagine you have a very big space with different rules. This space is called a Hilbert space. Inside this space there are special objects called operators that do things like rotate or stretch other objects in the space.

There are different ways to measure how close or far away these operators are from each other. Those ways are called topologies.

For example, if you want to compare two operators and see if they are similar or not, you can measure how much they change other objects they operate on. This is called the operator norm topology.

Another way to compare these operators is by how similar their eigenvectors are. Eigenvectors are like secret ingredients that make an operator work. This is called the strong topology.

Each topology has its own set of rules for measuring distances and determining what is close or far away. They are like different games with different rules.