All subsets of a set $X$ (its power set)
Terms
| Term | This example | Why |
|---|---|---|
| topology | ✓ | The power set of $X$ is a topology on $X$: the discrete topology, in which every set is open. |
| σ-algebra | ✓ | The power set of $X$ is a σ-algebra on $X$, because it contains every subset of $X$, so it is closed under every set operation. |