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    • CommentRowNumber1.
    • CommentAuthorUrs
    • CommentTimeAug 31st 2012

    wrote something at free abelian group. Not great, need to come back to this.

    • CommentRowNumber2.
    • CommentAuthorUrs
    • CommentTimeSep 6th 2012

    I have expanded at free abelian group a little. Just basic stuff.

    • CommentRowNumber3.
    • CommentAuthorUrs
    • CommentTimeJul 13th 2016
    • (edited Jul 13th 2016)

    added the statement that, assuming AC, every subgroup of a free abelian group is itself free abelian, here

    • CommentRowNumber4.
    • CommentAuthorTodd_Trimble
    • CommentTimeJul 13th 2016

    Just to let you know: we have a proof of the more general fact that submodules of free modules over a pid are free, here.

    • CommentRowNumber5.
    • CommentAuthorUrs
    • CommentTimeJul 13th 2016

    Thanks. I have added a cross-link.

    • CommentRowNumber6.
    • CommentAuthorDmitri Pavlov
    • CommentTimeFeb 1st 2021

    Redirect: free abelian group functor.

    diff, v9, current

    • CommentRowNumber7.
    • CommentAuthorTodd_Trimble
    • CommentTimeFeb 18th 2021

    Added some remarks to clarify that the notion of free abelian group does not depend on a specific choice of free functor.

    diff, v10, current

    • CommentRowNumber8.
    • CommentAuthorUrs
    • CommentTimeJul 12th 2021
    • (edited Jul 12th 2021)

    briefly added the statement (here) that forming free abelian groups sends Cartesian products to tensor products.

    diff, v14, current

    • CommentRowNumber9.
    • CommentAuthorUrs
    • CommentTimeApr 26th 2023

    below the remark that

    []:SetAb \mathbb{Z}[-] \;\colon\; Set \longrightarrow Ab

    is strong monoidal, I added, for completeness, the remark that hence also

    []:sSetsAb \mathbb{Z}[-] \;\colon\; sSet \longrightarrow sAb

    is strong monoidal (here)

    diff, v18, current