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1. • CommentRowNumber1.
   • CommentAuthornLab edit announcer
   • CommentTimeDec 29th 2020
   • PermaLink
   Author: nLab edit announcer
   Format: MarkdownItexAdd basic definition in context of algebraic topology. My first contribution. Grant <a href="https://ncatlab.org/nlab/revision/diff/null+homotopy/5">diff</a>, <a href="https://ncatlab.org/nlab/revision/null+homotopy/5">v5</a>, <a href="https://ncatlab.org/nlab/show/null+homotopy">current</a>

   Add basic definition in context of algebraic topology. My first contribution.

   Grant

   diff, v5, current

2. • CommentRowNumber2.
   • CommentAuthorUrs
   • CommentTimeDec 29th 2020
   • PermaLink
   Author: Urs
   Format: MarkdownItexThanks! I have added the remark that this is considered in particular for pointed topological spaces, in which case the maps constant on the base point are "[[zero morphisms]]". Also added a brief sentence on the general situation in abstract homotopy theory. <a href="https://ncatlab.org/nlab/revision/diff/null+homotopy/6">diff</a>, <a href="https://ncatlab.org/nlab/revision/null+homotopy/6">v6</a>, <a href="https://ncatlab.org/nlab/show/null+homotopy">current</a>

   Thanks!

   I have added the remark that this is considered in particular for pointed topological spaces, in which case the maps constant on the base point are “zero morphisms”.

   Also added a brief sentence on the general situation in abstract homotopy theory.

   diff, v6, current