(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”
Fascinating. I especially like the shadow-sculpture!
Btw. a “t” is missing from the “ist” in your title.
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.
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!)