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It is a known result that based point maps $f:S^2\to S^2$ are classified by their degree. That is, by the induced map at $\pi_2$-level $f_{*2}:\pi_2(S^2)\to\pi_2(S^2)$ (the subindex $*2$ just meanmeans it is the induced map by $f$ at $\pi_2$-level). However, I am interested in knowing which is the relationship (if there is any) between the induced maps $f_{*2}:\pi_2(S^2)\to\pi_2(S^2)$ and $f_{*3}:\pi_3(S^2)\to\pi_3(S^2)$. For instance, if the former is the zero map it means that $f$ is null-homotopic and therefore the latter should also be the zero map. But, it they are not zero, how are they related? Thanks in advance.

It is a known result that based point maps $f:S^2\to S^2$ are classified by their degree. That is, by the induced map at $\pi_2$-level $f_{*2}:\pi_2(S^2)\to\pi_2(S^2)$ (the subindex $*2$ just mean it is the induced map by $f$ at $\pi_2$-level). However, I am interested in knowing which is the relationship (if there is any) between the induced maps $f_{*2}:\pi_2(S^2)\to\pi_2(S^2)$ and $f_{*3}:\pi_3(S^2)\to\pi_3(S^2)$. For instance, if the former is the zero map it means that $f$ is null-homotopic and therefore the latter should also be the zero map. But, it they are not zero, how are they related? Thanks in advance.

It is a known result that based point maps $f:S^2\to S^2$ are classified by their degree. That is, by the induced map at $\pi_2$-level $f_{*2}:\pi_2(S^2)\to\pi_2(S^2)$ (the subindex $*2$ just means it is the induced map by $f$ at $\pi_2$-level). However, I am interested in knowing which is the relationship (if there is any) between the induced maps $f_{*2}:\pi_2(S^2)\to\pi_2(S^2)$ and $f_{*3}:\pi_3(S^2)\to\pi_3(S^2)$. For instance, if the former is the zero map it means that $f$ is null-homotopic and therefore the latter should also be the zero map. But, it they are not zero, how are they related? Thanks in advance.

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Relationship between induced maps at homotopy groups level for maps$fmaps $f:S^2\to S^2$

It is a known result that based point maps $f:S^2\to S^2$ are classified by their degree. That is, by the induced map at $\pi_2-$$\pi_2$-level $f_{*2}:\pi_2(S^2)\to\pi_2(S^2)$ (the subindex $*2$ just mean it is the induced map by $f$ at $\pi_2$-level). However, iI am interested in knowing which is the relationship (if there is any) between the induced maps $f_{*2}:\pi_2(S^2)\to\pi_2(S^2)$ and $f_{*3}:\pi_3(S^2)\to\pi_3(S^2)$. For instance, if the former is the zero map it means that $f$ is nullhomotopicnull-homotopic and therefore the latter should also be the zero map. But, it they are not zero, how are they related? Thanks in advance.

Relationship between induced maps at homotopy groups level for maps$f:S^2\to S^2$

It is a known result that based point maps $f:S^2\to S^2$ are classified by their degree. That is, by the induced map at $\pi_2-$level $f_{*2}:\pi_2(S^2)\to\pi_2(S^2)$ (the subindex $*2$ just mean it is the induced map by $f$ at $\pi_2$-level). However, i am interested in knowing which is the relationship (if there is any) between the induced maps $f_{*2}:\pi_2(S^2)\to\pi_2(S^2)$ and $f_{*3}:\pi_3(S^2)\to\pi_3(S^2)$. For instance, if the former is the zero map it means that $f$ is nullhomotopic and therefore the latter should also be the zero map. But, it they are not zero, how are they related? Thanks in advance.

Relationship between induced maps at homotopy groups level for maps $f:S^2\to S^2$

It is a known result that based point maps $f:S^2\to S^2$ are classified by their degree. That is, by the induced map at $\pi_2$-level $f_{*2}:\pi_2(S^2)\to\pi_2(S^2)$ (the subindex $*2$ just mean it is the induced map by $f$ at $\pi_2$-level). However, I am interested in knowing which is the relationship (if there is any) between the induced maps $f_{*2}:\pi_2(S^2)\to\pi_2(S^2)$ and $f_{*3}:\pi_3(S^2)\to\pi_3(S^2)$. For instance, if the former is the zero map it means that $f$ is null-homotopic and therefore the latter should also be the zero map. But, it they are not zero, how are they related? Thanks in advance.

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X1921
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It is a known result that based point maps $f:S^2\to S^2$ are classified by their degree. That is, by the induced map at $\pi_2-$level $f_{*2}:\pi_2(S^2)\to\pi_2(S^2)$ (the subindex $*2$ just mean it is the induced map by $f$ at $\pi_2$-level). However, i am interested in knowing which is the relationship (if there is any) between the induced maps $f_{*2}:\pi_2(S^2)\to\pi_2(S^2)$ and $f_{*3}:\pi_3(S^2)\to\pi_3(S^2)$. For instance, if the former is the zero map it means that $f$ is nullhomotopic and therefore the latter should also be the zero map. But, it they are not zero, which is their relationshiphow are they related? Thanks in advance.

It is a known result that based point maps $f:S^2\to S^2$ are classified by their degree. That is, by the $f_{*2}:\pi_2(S^2)\to\pi_2(S^2)$. However, i am interested in knowing which is the relationship (if there is any) between the induced maps $f_{*2}:\pi_2(S^2)\to\pi_2(S^2)$ and $f_{*3}:\pi_3(S^2)\to\pi_3(S^2)$. For instance, if the former is the zero map it means that $f$ is nullhomotopic and therefore the latter should also be the zero map. But, it they are not zero, which is their relationship? Thanks in advance.

It is a known result that based point maps $f:S^2\to S^2$ are classified by their degree. That is, by the induced map at $\pi_2-$level $f_{*2}:\pi_2(S^2)\to\pi_2(S^2)$ (the subindex $*2$ just mean it is the induced map by $f$ at $\pi_2$-level). However, i am interested in knowing which is the relationship (if there is any) between the induced maps $f_{*2}:\pi_2(S^2)\to\pi_2(S^2)$ and $f_{*3}:\pi_3(S^2)\to\pi_3(S^2)$. For instance, if the former is the zero map it means that $f$ is nullhomotopic and therefore the latter should also be the zero map. But, it they are not zero, how are they related? Thanks in advance.

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