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I apologize in advance if this question is too technical. I haven't found a reference in the literature yet, and it seems difficult enough that perhaps it has not been answered.

Let $A$, $B$, and $C$ be based topological spaces, all compactly generated and weak Hausdorff. Let $\wedge$ and $F$ denote smash product and space of based functions, respectively, modified in the usual way so as to produce CGWH spaces. Consider the "assembly" map $$ A \wedge F(B,C) \rightarrow F(B, A \wedge C) $$ It is the adjoint of the smash product of the identity of $A$ and the evaluation map of $F(B,C)$.

Is this map always a closed inclusion?

(It is not hard to show that it is injective, has closed image, and that if $K$ is a closed subset of the domain, then $K \cup \{*\}$ is a closed subset of the codomain. If you take $A$, $B$, and $C$ to be $[0,\infty)$, you appear to get a counterexample.)

EDIT: I believed earlier that this counterexample could maybe be fixed by making everything compactly generated, but only ifthat doesn't help, you usecan still produce a non-convergent sequence in the ordinary topology on $F(B,A \wedge C)$source that converges in the target to the basepoint, and this still produces a closed set whose image is not the compactly-generated one closed.) So this is actually not true! Juan, thanks for pointing me to Lewis's thesis.

I apologize in advance if this question is too technical. I haven't found a reference in the literature yet, and it seems difficult enough that perhaps it has not been answered.

Let $A$, $B$, and $C$ be based topological spaces, all compactly generated and weak Hausdorff. Let $\wedge$ and $F$ denote smash product and space of based functions, respectively, modified in the usual way so as to produce CGWH spaces. Consider the "assembly" map $$ A \wedge F(B,C) \rightarrow F(B, A \wedge C) $$ It is the adjoint of the smash product of the identity of $A$ and the evaluation map of $F(B,C)$.

Is this map always a closed inclusion?

(It is not hard to show that it is injective, has closed image, and that if $K$ is a closed subset of the domain, then $K \cup \{*\}$ is a closed subset of the codomain. If you take $A$, $B$, and $C$ to be $[0,\infty)$, you appear to get a counterexample, but only if you use the ordinary topology on $F(B,A \wedge C)$ and not the compactly-generated one.)

I apologize in advance if this question is too technical. I haven't found a reference in the literature yet, and it seems difficult enough that perhaps it has not been answered.

Let $A$, $B$, and $C$ be based topological spaces, all compactly generated and weak Hausdorff. Let $\wedge$ and $F$ denote smash product and space of based functions, respectively, modified in the usual way so as to produce CGWH spaces. Consider the "assembly" map $$ A \wedge F(B,C) \rightarrow F(B, A \wedge C) $$ It is the adjoint of the smash product of the identity of $A$ and the evaluation map of $F(B,C)$.

Is this map always a closed inclusion?

(It is not hard to show that it is injective, has closed image, and that if $K$ is a closed subset of the domain, then $K \cup \{*\}$ is a closed subset of the codomain. If you take $A$, $B$, and $C$ to be $[0,\infty)$, you appear to get a counterexample.)

EDIT: I believed earlier that this counterexample could maybe be fixed by making everything compactly generated, but that doesn't help, you can still produce a non-convergent sequence in the source that converges in the target to the basepoint, and this still produces a closed set whose image is not compactly closed. So this is actually not true! Juan, thanks for pointing me to Lewis's thesis.

added algebraic topology tag (where smash products are of the most interest)
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Source Link
Cary
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  • 18

is this map a closed inclusion?

I apologize in advance if this question is too technical. I haven't found a reference in the literature yet, and it seems difficult enough that perhaps it has not been answered.

Let $A$, $B$, and $C$ be based topological spaces, all compactly generated and weak Hausdorff. Let $\wedge$ and $F$ denote smash product and space of based functions, respectively, modified in the usual way so as to produce CGWH spaces. Consider the "assembly" map $$ A \wedge F(B,C) \rightarrow F(B, A \wedge C) $$ It is the adjoint of the smash product of the identity of $A$ and the evaluation map of $F(B,C)$.

Is this map always a closed inclusion?

(It is not hard to show that it is injective, has closed image, and that if $K$ is a closed subset of the domain, then $K \cup \{*\}$ is a closed subset of the codomain. If you take $A$, $B$, and $C$ to be $[0,\infty)$, you appear to get a counterexample, but only if you use the ordinary topology on $F(B,A \wedge C)$ and not the compactly-generated one.)