Simple connectedness
Semilocal simple connectedness
A topological space 𝑋 is called semilocally simply connected iff every 𝑥 ∈𝑋 has an open neighbourhood 𝑈 ⊆𝑋 so that every continuous loop in 𝑈 is null-homotopic in 𝑋,
#m/def/topology
i.e. if 𝜄 :(𝑈,𝑥) ↪(𝑋,𝑥) is the natural inclusion then 𝜋1𝜄 :𝜋1(𝑈,𝑥) →𝜋1(𝑋,𝑥) is the trivial homomorphism.
Properties
#state/tidy | #lang/en | #SemBr