A chain homotopy between two chain homomorphisms and
is a sequence
of group homomorphisms or module
homomorphisms, according to the category of the
chain complexes,
where
denotes the boundary operator.
A chain homotopy between two chain homomorphisms and
is a sequence
of group homomorphisms or module
homomorphisms, according to the category of the
chain complexes,
where
denotes the boundary operator.
Portions of this entry contributed by Todd Rowland
Weisstein, Eric W., with contributions by Todd Rowland. "Chain Homotopy." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/ChainHomotopy.html