The smooth vector fields on a manifold $M$, as a module over the ring of smooth functions on $M$
Terms
| Term | This example | Why |
|---|---|---|
| module | ✓ | The smooth vector fields on a manifold $M$ form a module over the smooth functions on $M$, because the product $f X$ of a smooth function $f$ and a smooth vector field $X$ is a smooth vector field. The smooth functions form a ring but not a field, because a function that is $0$ somewhere has no multiplicative inverse. |