Definition
Given elements, the Whitehead bracket
is defined as follows:
The product can be obtained by attaching a -cell to the wedge sum
- ;
the attaching map is a map
Represent and by maps
and
then compose their wedge with the attaching map, as
The homotopy class of the resulting map does not depend on the choices of representatives, and thus one obtains a well-defined element of
Read more about this topic: Whitehead Product
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