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Oct 7, 2015 at 6:03 comment added user51223 @NajibIdrissi We known there is a fibration such as $SO(n-1)\to SO(n)\to S^{n-1}$. If you assume that the decomposition holds, then your input data are: the existence of the fibration and the decomposition of its total as the product of fibre and base, by which you to find a section easily. This situation is slightly different from what you have asked and the upcoming answers afterwards.
Oct 6, 2015 at 13:17 comment added Achim Krause Nope, not true in general: Take a countable union of copies of $S^1$ and define a map $\cup S^1\rightarrow S^1$ by the double cover $S^1\rightarrow S^1$ on each summand. The fiber is countably many points, the total space is a product of countably many points with $S^1$, but there's no section.
Oct 6, 2015 at 12:46 comment added Najib Idrissi This is probably a naive question, but is it always true that if $C \cong A \times B$, then any fibration $A \to C \to B$, but where the maps involved are not necessarily the canonical ones, always admits a section?
Oct 6, 2015 at 12:28 history answered user51223 CC BY-SA 3.0