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1. • CommentRowNumber1.
   • CommentAuthorUrs
   • CommentTimeJan 26th 2021
   • (edited Jan 26th 2021)
   • PermaLink
   Author: Urs
   Format: MarkdownItexThe first line of the Idea-section read: > Every [[magma]] $A$ has an _opposite_ $A^op$ in which the operation goes the other direction. This rather sounded like talking about co-magmas. I have replaced this now with the following more lengthy but less ambiguous sentence: > The _opposite_ of a magma -- hence of a set with a binary operation $(x,y) \mapsto x y$ -- has the same underlying set of elements, but binary operation changed by _reversing the order_ of the factors: $(x,y) \mapsto y x$. Also I touched the Definition-section, trying to beautify a little, both the wording and the formulas. <a href="https://ncatlab.org/nlab/revision/diff/opposite+magma/4">diff</a>, <a href="https://ncatlab.org/nlab/revision/opposite+magma/4">v4</a>, <a href="https://ncatlab.org/nlab/show/opposite+magma">current</a>

   The first line of the Idea-section read:

   Every magma $A$ has an opposite $A^op$ in which the operation goes the other direction.

   This rather sounded like talking about co-magmas. I have replaced this now with the following more lengthy but less ambiguous sentence:

   The opposite of a magma – hence of a set with a binary operation $(x,y) \mapsto x y$ – has the same underlying set of elements, but binary operation changed by reversing the order of the factors: $(x,y) \mapsto y x$.

   Also I touched the Definition-section, trying to beautify a little, both the wording and the formulas.

   diff, v4, current