PlanetPhysics/Cubically Thin Homotopy 2
Cubically thin homotopy
editLet be squares in with common vertices.
- A {\it cubically thin homotopy}
between and is a cube such that
#
- is a homotopy between and
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- is rel. vertices of
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- the faces are thin for .
- The square is {\it cubically} -{\it equivalent} to
denoted if there is a cubically thin homotopy between and
This definition enables one to construct , by defining a relation of cubically thin homotopy on the set of squares.