nLab
Hurewicz fibration

Contents

Definition

A Hurewicz fibration p:EB is a continuous map of topological spaces that satisfies the right lifting property with respect to maps σ 0:XX×{0}X×I for all topological spaces X.

This right lifting property is in this context called the homotopy lifting property, because the maps from X×I are understood as homotopies. In more detail, for every space X, any homotopy F:X×IB, and a continuous map f:XE, there is a homotopy F˜:X×IE such that f=F˜σ 0:=F˜ 0 and F=pF˜:

X f E σ 0 F˜ p X×I F B.\array{ X &\stackrel{f}\to& E \\ \downarrow^{\sigma_0} &{}^{\tilde{F}}\nearrow& \downarrow^p \\ X\times I &\stackrel{F}{\to}& B } \,.

Instead of checking the homotopy lifting property, one can instead solve a universal problem, see Hurewicz connection.

Appearance in a model structure

There is a Quillen model category structure on Top where fibrations are Hurewicz fibrations, cofibrations are closed Hurewicz cofibrations and weak equivalences are homotopy equivalences; see model structure on topological spaces and Strøm's model category. There is a version of Hurewicz fibrations for pointed spaces, as well as in the slice category Top/B 0 where B 0 is a fixed base.

References

The historical paper of Hurewicz is

  • Witold Hurewicz, On the concept of fiber space, Proc. Nat. Acad. Sci. USA 41 (1955) 956–961; MR0073987 (17,519e) PNAS,pdf.

Hurewicz fibrations are nowdays a standard topic in textbooks of algebraic topology (Whitehead, Spanier, Hatcher…).