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    • CommentRowNumber1.
    • CommentAuthorTim_Porter
    • CommentTimeApr 12th 2020

    Following his passing yesterday from Covid-19, I have added a bit more on his contributions that are relevant to the nPOV.

    diff, v3, current

    • CommentRowNumber2.
    • CommentAuthorUrs
    • CommentTimeApr 12th 2020

    What’s your source for the cause of death?

    • CommentRowNumber3.
    • CommentAuthorRodMcGuire
    • CommentTimeApr 12th 2020

    his death only seems to be on twitter now

    Sam Wang at Princeton

    I am sorry to confirm the passing of my colleague John Conway. An incomparable mathematician, a pleasant neighbor, and an excellent coffee acquaintance.

    His passing was sudden (fever started only Wednesday morning). Part of coronavirus’s hard toll in New Jersey.

    • CommentRowNumber4.
    • CommentAuthorUrs
    • CommentTimeApr 12th 2020

    Yeah. Careful with Twitter rumours. It could be true. Or not.

    • CommentRowNumber5.
    • CommentAuthorDavidRoberts
    • CommentTimeApr 13th 2020

    It’s on Wikipedia now, with sources.

    • CommentRowNumber6.
    • CommentAuthorUrs
    • CommentTimeApr 14th 2020

    Wikipedia only points to a Dutch newspaper article. That seems less reliable even than the original tweet, whose author at least seemed to have had some first hand information.

    Clearly it doesn’t matter here either way.

    But I find it disconcerting that in a most extraordinary situation which is all predicated on sorting out a subtle empirical analysis X, people feel at ease with throwing around assertions of X based on nothing.

    • CommentRowNumber7.
    • CommentAuthorDavidRoberts
    • CommentTimeApr 14th 2020
    • CommentRowNumber8.
    • CommentAuthorGuest
    • CommentTimeApr 14th 2020
    I first met John Conway while he was manning a stall for the Archimedeans at the beginning-of-the-year student fair in the Guildhall in Cambridge. He was demonstrating a computer, built of string and meccano, that had to be fed ball-bearings. I think it was 1957. One of the first mathematical lollipops he showed me was a very slick proof that a triangle of nonzero area whose sides were in rational proportion and whose angles were in rational proportion must be equilateral. Hint: the cyclotomic field of N-th roots of unity has \phi(N) automorphisms. But ruler-and-compass construction shows that there can only be 2 triangles with given sides. So N has to be 3 times a power of 2. In those days it was knots and sphere-packing. Later came games. For years he had a running exchange of puzzles with someone in the North of England who made them as toys. He was very hands-on: popper beads for demonstrating knots and links, and strange wooden devices for calculating the touching-graph of circle-packings using pennies and a ruler to shove them up tight. The last time I saw him not in the Mill Lane maths department tearoom he was tiling his kitchen floor with Penrose kites and darts. My mother used to babysit his daughters. Some of the faculty at Cambridge thought that he was a disturbing influence on their students; not serious enough. --Gavin Wraith
    • CommentRowNumber9.
    • CommentAuthorTodd_Trimble
    • CommentTimeApr 15th 2020

    Thank you, Gavin, for your reminiscences. I think everyone who came into contact with Conway came away astonished at the sparkle and effervescence of his genius.

  1. Taking the liberty of adding Gavin Wraith’s reminiscences to the entry. Broke it up into a few paragraphs; feel free to edit!

    diff, v4, current

    • CommentRowNumber11.
    • CommentAuthorTobyBartels
    • CommentTimeApr 27th 2020

    Not to be confused with John B. Conway, the analyst.

    diff, v5, current

    • CommentRowNumber12.
    • CommentAuthorDmitri Pavlov
    • CommentTimeApr 27th 2020

    Moved the disambiguation line to the top of the article as is standard on the nLab.

    diff, v6, current

    • CommentRowNumber13.
    • CommentAuthorDmitri Pavlov
    • CommentTimeApr 27th 2020

    Renamed the page to indicate the full name. Added redirects.

    diff, v6, current

    • CommentRowNumber14.
    • CommentAuthorDmitri Pavlov
    • CommentTimeApr 27th 2020

    Something strange happened: TeX commands like \section{…} no longer work in this article. They did work in the previous versions.

    • CommentRowNumber15.
    • CommentAuthorTobyBartels
    • CommentTimeApr 27th 2020

    Thanks, Dmitri.

    Control characters in the first line often break things. For this reason, I always put a blank line at the beginning (and end) of every article. This seems to have fixed things here.

    • CommentRowNumber16.
    • CommentAuthorSamuel Adrian Antz
    • CommentTimeJun 10th 2024
    • (edited Jun 10th 2024)

    Added paper about platycosms (including the Hantzsche-Wendt manifold):

    diff, v9, current