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rgnrmllbrg
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Map from $\mathbb{S}^k$ with lifting property induces surjections on homotopy groups. Is it weak equivalence?

Let $q\colon \mathbb{S}^k\to X$ be a map such that given any continuous $f\colon K\to X$ from a compact space $K$, there exists (a non-unique) $\tilde{f}\colon K\to \mathbb{S}^k$ with $q\tilde{f}=f$. Assume also that $X$ is a CW complex, but possibly infinite-dimensional.

Can we say anything at all about the homotopy groups of $X$ besides that they must be quotients of the homotopy groups of $\mathbb{S^k}$?

I apologize if this is too easy for the forum, this is not my area.

rgnrmllbrg
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