Desuspensions of S^1 /\ P^1_Q-{0,1,infty}

We use the Galois action on $π_1^{\textrm{et}}(\mathbb{P}_{\overline{\mathbb{Q}}}^1 - \{0,1,\infty \})$ to show that the homotopy equivalence $S^1 \wedge (\mathbb{G}_{m,\mathbb{Q}} \vee \mathbb{G}_{m,\mathbb{Q}}) \cong S^1 \wedge (\mathbb{P}_{\mathbb{Q}}^1 - \{0,1,\infty \})$ coming from purity does not desuspend to a map $\mathbb{G}_{m,\mathbb{Q}} \vee \mathbb{G}_{m,\mathbb{Q}} \to \mathbb{P}_{\mathbb{Q}}^1 - \{0,1,\infty \}$.

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