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Pseudospheres are basically just the hyperbolic planes I've crocheted up before only this time in a spiral. Historically they are the first shapes that were hypothesized as examples of non-euclidean surfaces with negative curvature.

Practically speaking it's difficult to know when to stop crocheting up a pseudosphere...

This entry was originally posted at http://purplecat.dreamwidth.org/29537.html.

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From:

bigtitch.livejournal.com

They're very pretty.

Practically speaking it's difficult to know when to stop crocheting up a pseudosphere...
Ah yes, classically the only limits to non-euclidean geometry has always been the supply of yarn.. ;)

From:

purplecat

I was actually persuaded to stop before I had run out of yarn but only on the grounds that the circumference of the pseudosphere was now the same length as the pattern on the yarn!

From:

lukadreaming.livejournal.com

I remember what negative curvature is!

From:

purplecat

Glad to know some of it is sticking!

From:

wellinghall.livejournal.com

Have you seen these?
http://www.kleinbottle.com/klein_bottle_hats.htm

From:

purplecat

I'd not. The book has instructions for crocheting a klein bottle, though you have to make two Mobius strips first.

From:

fredbassett

I just keep wondering wht you're going to do with them all!

From:

purplecat

I'm wondering that, especially since we don't really go in for trinkets.

From:

wellinghall.livejournal.com

And then there's this ...

http://www.etsy.com/listing/33976760/two-headed-black-snake-scarf?ref=sr_gallery_1&ga_search_query=snake+two+headed&ga_search_type=handmade&ga_page=&order=&includes[0]=tags&includes[1]=title&filter[0]=handmade

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