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PhilipM
11-16-2005, 02:45 PM
I didn't see this here, but thought people may be interested:

Britney Gallivan has solved the Paper Folding Problem. This well known challenge was to fold paper in half more than seven or eight times, using paper of any size or shape.
http://pomonahistorical.org/12times.htm

Captain Amazing
11-16-2005, 02:48 PM
Good for her, I guess. Is there a question?

Tevildo
11-16-2005, 02:50 PM
Looking at the diagram, it seems to take a fairly liberal approach to the definition of "in half".

PhilipM
11-16-2005, 02:56 PM
no question... statement... got a better forum to put it in?

Captain Amazing
11-16-2005, 02:56 PM
no question... statement... got a better forum to put it in?
MPSIMS?

Jpeg Jones
11-16-2005, 03:02 PM
Yowza! I'd let her fold me in half 27 times!

Hampshire
11-16-2005, 03:09 PM
How about a piece of paper 300' x 2".
Could you fold that in half 8 times and end up with a wad of paper 2" x a little over a foot?

tanstaafl
11-16-2005, 03:11 PM
I would guess this is about one of Cecil's columns...

http://www.straightdope.com/classics/a910705.html

PhilipM
11-16-2005, 03:14 PM
RIGHT! I knew I'd seen it somewhere but couldn't find it immediately and was too lazy to search much.

Giles
11-16-2005, 03:42 PM
The largest pieces of paper generally available would be the rolls of newsprint that are used for printing newspapers. These weigh around 25 tonnes -- there are pictures here. (http://www.howesoundpp.com/virtualtour/vt01_newsmachine.htm)

According to this page (near the bottom) (http://www.borealforest.org/paper/mill.htm), such pieces of paper are about 65 kilometres in length. Foled in halp 12 times, and the pile would be still be about 16 metres wide. However, one person could not do that folding without the use of mechanical handling equipment, such as a crane capable of lifting around 15 tonnes.

Beware of Doug
11-16-2005, 03:54 PM
I could think about this problem for weeks and never would it occur to me to use math. I'd be using soup spoons, dictionaries, anvils, driving cars over the damn piece of paper...but an equation? Lands sakes.

Atticus Finch
11-16-2005, 04:14 PM
I read the link and saw that she'd applied maths to prove something or other, but how did it help her physically fold the paper?

Bryan Ekers
11-16-2005, 04:18 PM
I read the link and saw that she'd applied maths to prove something or other, but how did it help her physically fold the paper?

She got a bunch of male applied maths students to help her, which wasn't difficult since they'll do anything just to get near a girl.

Mangetout
11-16-2005, 04:43 PM
Looking at the diagram, it seems to take a fairly liberal approach to the definition of "in half".Also a rather liberal definition of 'fold' - that's the big thing about the paper folding problem that most people don't seem to appreciate; it isn't just that the object you're trying to manipulate is steadily getting smaller, it's that the number of sheets you're trying to fold is doubling every time - more than seven folds and it isn't really a 'fold' any more, it's a 'bend', at least for the sheets on the outside.

Mathochist
11-16-2005, 06:23 PM
She got a bunch of male applied maths students to help her, which wasn't difficult since they'll do anything just to get near a girl.

Yeah, yeah. Mathematics students are all socially inept and easily manipulated. Got any more stereotypes you want to throw around?

Mathochist
11-16-2005, 06:30 PM
I didn't see this here, but thought people may be interested:

Britney Gallivan has solved the Paper Folding Problem. This well known challenge was to fold paper in half more than seven or eight times, using paper of any size or shape.
http://pomonahistorical.org/12times.htm

A big error on the site (reads like a press release) is that she "was the first person to realize the basic cause for the limits." This is plainly false. She may be the first person to bother carrying through the calculation, but just because mathematicians haven't worked out the numbers on a niche problem doesn't mean they don't realize the technique that will lead to the answer. She may be able to stretch this into a master's thesis at a place like Pomona College, but it's really no more than an exercise nobody had bothered to actually carry out before because there's nothing to be done with it.

Bryan Ekers
11-16-2005, 06:42 PM
Yeah, yeah. Mathematics students are all socially inept and easily manipulated. Got any more stereotypes you want to throw around?

Well, there's the left-handed anabaptists....

Derleth
11-16-2005, 08:03 PM
Yeah, yeah. Mathematics students are all socially inept and easily manipulated. Got any more stereotypes you want to throw around?Eh, what do you expect from a Montrealer?

;)

mrrealtime
11-16-2005, 09:06 PM
I am always amazed to see new breakthroughs.. This probably has some implications for nanotechnology and building stuff at a molecular level, not to mention folding solar sails...thanks for posting! I've ordered her book.

Bryan Ekers
11-17-2005, 01:44 AM
Eh, what do you expect from a Montrealer?

;)

Oh, for crying out Glavin....

ZenBeam
11-17-2005, 11:48 AM
How about a piece of paper 300' x 2".
Could you fold that in half 8 times and end up with a wad of paper 2" x a little over a foot?I've got a sheet of notebook paper that I folded in half 8 times. It's only about 3/4 inches tall.

mrrealtime
11-18-2005, 08:49 AM
This morning I was able to fold a single ply of tissue paper (kleenex) 10 times. It was about 3/4 " thick.

Chronos
11-18-2005, 12:47 PM
I read the link and saw that she'd applied maths to prove something or other, but how did it help her physically fold the paper?It told her how big the paper had to be, before she started.

And as the link points out, it's not a matter of strength. If you take a paper that's too small to start with, and put it under a hydraulic diamond press for the last steps, it might rip apart, but it won't fold.

Personally, by the way, I have no objection to her standard of "folding". Any attempt at a stricter definition will end up implying that you can't fold a piece of paper in half twice, since the outer layer will be "bending" around the middle layers, not "folding".

DanBlather
11-18-2005, 01:01 PM
Yeah, yeah. Mathematics students are all socially inept and easily manipulated. Got any more stereotypes you want to throw around?Math student: I'll never reach her.
Eng Srudent: Yeah, but I'll get close enough

VegaBean
11-23-2005, 07:56 PM
Seems like the main problem is that half way through you need extra paper for the later curves but there is no place to "store" it.

It's pretty obvious that you could have the end result of as many folds as you wanted, but the problem is that during the actual folding there would be huge bulges in the work.

For example, if you wanted to do 15 folds, you would create an end-wise drawing like in tis picture http://pomonahistorical.org/FoldDiagramBCG.gif.
Put pegs into a wall at all the turn points.
Then just start threading the paper following the lines, like feeding the film into an old 8mm projector.

Once it was in place, you might fool some people right there. If they demanded proof of folding, you might think that you could simply grab the finished pile, start unfolding for the camera, and then run the tape backward.

But what you would find is that at the first step of unfolding you would have huge bulges on each half. Unfolding them would create impossible convolutions, and at that stage it would be clear that your process would bind up and block its own undoing.