Die kleinsche Flasche ist keine riemannsche Fläche

(Or in other words, the Klein bottle

is not a Riemann surface…)

I bought this little marvel in the shop of the excellent Giessen Mathematikum math museum. My two favorite exhibits were this playful shadow (a sculpture of Larry Kagan)

and a rather thought-provoking physical illustration of what is a “one in a million chance”

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I am a professor of mathematics at ETH Zürich since 2008.

4 thoughts on “Die kleinsche Flasche ist keine riemannsche Fläche”

  1. Fascinating. I especially like the shadow-sculpture!

    Btw. a “t” is missing from the “ist” in your title.

  2. Very nice! I got my Klein bottle (actually, my wife got it for me for Christmas) from kleinbottle.com, which is a web site well worth browsing.

  3. Oups, thanks for pointing out the typo in the title! (Since I just came back from my summer German-language course, this was particularly embarrassing!)

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