Definition:Fiber Bundle

Definition
Let $M, E, F$ be topological spaces.

Let $\pi : E \to M$ be a continuous surjection.

Let $I$ be some index set and let $\mathfrak U := \left\{ {U_\alpha \subseteq M} \middle\vert {\alpha \in I } \right\}$ be an open cover, such that $\forall \alpha \in I$ there exist homeomorphisms


 * $\displaystyle \chi_\alpha : \pi^{-1}\left( {U _\alpha }\right) \to U_\alpha \times F$

satisfying $\pi {\restriction}_{U_ \alpha}= \mathrm{pr}_{1,\alpha} \circ \chi_ \alpha$ on $\pi^{-1} \left({ U_\alpha }\right)$ for all $\alpha \in I$, where


 * $\displaystyle \mathrm{pr}_{1,\alpha} : U_\alpha \times  F \to U_\alpha $

is the $1$st projection.

Then the tuple $(E,M,F,\pi)$ is called a fiber bundle.

$E$ is called the total space over the base space $M$.

$F$ is called the fiber.

$\pi$ is called the bundle projection.

$\pi^{-1}\left( { m }\right)$ is called the fiber over the base point $m \in M$.

$\chi_\alpha$ is called a local trivialization.

$\chi_\beta \circ \chi_\alpha^{-1}$ is called a transition map.