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nLab > Latest Changes: opposite magma

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  1.  
    • CommentRowNumber1.
    • CommentAuthorUrs
    • CommentTimeJan 26th 2021
    • (edited Jan 26th 2021)

    The first line of the Idea-section read:

    Every magma A has an opposite Aop 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)↦xy – has the same underlying set of elements, but binary operation changed by reversing the order of the factors: (x,y)↦yx.

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

    diff, v4, current

  2. typo

    shirAko

    diff, v6, current

    • CommentRowNumber3.
    • CommentAuthorvarkor
    • CommentTimeMay 27th 2025
    • (edited May 27th 2025)

    Added cross-reference to reverse monoidal category. It’s a little confusing that the two terminologies do not match: it would be more consistent to call this the reverse magma, rather than the opposite magma. I do not know whether there is precedent for this in the literature, though.

    diff, v7, current

1 to 3 of 3

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