Section (fiber bundle)
In the mathematical field of topology, a section (or cross section) of a fiber bundle E {\displaystyle E} is a continuous right inverse of the projection function π {\displaystyle \pi } . In other words, if E {\displaystyle E} is a fiber bundle over a base space, B {\displaystyle B} : π : E → B {\displaystyle \pi \colon E\to B} then a section of that fiber bundle is a continuous map, σ : B → E {\displaystyle \sigma \colon B\to E} such that π ( σ ( x ) ) = x {\displaystyle \pi (\sigma (x))=x} for all x ∈ B {\displaystyle x\in B} .