annathyst: (Default)
Anna ([personal profile] annathyst) wrote2005-11-14 03:13 am

topology exam

Good enough for partial credit. I didn't like Problem 2.
Close enough to being done that I can go to sleep and then hand it in in sure knowledge that I'll pass.

Night.

[identity profile] http://users.livejournal.com/butter_fly_/ 2005-11-14 01:16 pm (UTC)(link)
explain the doughnut one to me later? i'm curious.

[identity profile] billemon.livejournal.com 2005-11-14 04:50 pm (UTC)(link)
The sides and top/bottom of the tic tac toe grid join up when you wrap it around a donut. So there are extra "diagonals" because
X--
--X
-X-
is actually the same as
--X
-X-
X--
. It would work better with pictures, I guess :)

[identity profile] billemon.livejournal.com 2005-11-14 05:15 pm (UTC)(link)
OK, Klein bottle makes my brain hurt, but it's a single surface, so you could do the same thing, couldn't you? *flounders* This is why I did CS and not math lol.
slab: (Default)

[personal profile] slab 2005-11-14 05:54 pm (UTC)(link)
Mmm... forbidden Klein bottle...

[identity profile] billemon.livejournal.com 2005-11-14 06:10 pm (UTC)(link)
Ahhhhhhh. but the twist puts you on the back of the board, and the next twist puts you back on the front the right way up :D:D you can just treat it the same .. </cheat>

[identity profile] billemon.livejournal.com 2005-11-14 11:30 pm (UTC)(link)
I do - thanks. Topology always tied my head in knots, I'm afraid. That made sense though.