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Hatcher-Algebraic-Topology
· Problem 1.3.9
The Fundamental Group
Mathematics — Graph Theory · covering-spaces
Problem
Show that if a path-connected, locally path-connected space
X
X
X
has
π
1
(
X
)
\pi_1(X)
π
1
(
X
)
finite, then every map
X
→
S
1
X \to S^1
X
→
S
1
is nullhomotopic. [Use the covering space
R
→
S
1
\mathbb{R} \to S^1
R
→
S
1
.]
Related theory
covering-spaces
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