Re:How to Slice a Bagel into Two Linked Halves (2009)
by ihaveajob on Friday January 26, 2018 @01:09PM
(#16241411)
Exercise to the reader: How do you slice the bagel so that you can spread cream cheese continuously along both sides. In other words, can you make a Möbious bagel?
Re:How to Slice a Bagel into Two Linked Halves (2009)
by wlesieutre on Friday January 26, 2018 @05:05PM
(#16243275)
Make a cut through it shaped like a mobius strip - that is, a single 180 degree rotation instead of going the whole 360 degrees shown here.
To think about it another way, imagine if you took a mobius strip and constructed a semicircular lump of bread on the surface, extending it around until it connects back to itself. You've made a bagel!
Now take the mobius strip out of the middle, and the gap it leaves is the cut you're asking to make.
Re:How to Slice a Bagel into Two Linked Halves (2009)
by wlesieutre on Saturday January 27, 2018 @01:44AM
(#16245151)
Potentially interesting to anyone with an oven, if you can capture 1% of that market you'll be rich!
I'd suggest raising a few million in seed funding and renting an office in downtown SF. If it doesn't pan out you can pivot into math-related silicone ice cube trays.
Re:How to Slice a Bagel into Two Linked Halves (2009)
by hawktheslayer on Friday January 26, 2018 @01:15PM
(#16241467)
My team at work thinks of every excuse possible to get bagels. Recently for a birthday, a work anniversary, and being restacked into new cubes. But this is the best possible excuse for bringing in bagels again on Monday.
Re:How to Slice a Bagel into Two Linked Halves (2009)
by curiousGambler on Friday January 26, 2018 @01:13PM
(#16241449)
Bagel, lox, cucumber and cream cheese has become my new favorite thing lately (bonus points for a squeeze of lemon, capers or some red onion if those things are to be found).
However, I of course have no bagels or bagel accessories on the one day I read about mathematically correct bagels :(
Re:How to Slice a Bagel into Two Linked Halves (2009)
by mabbo on Friday January 26, 2018 @01:08PM
(#16241396)
I wonder if it's possible to repeat the process in such a way that you make a chain. I'm trying to visualize how but I'm not certain whether it could only make more links all attached in the same place.
Re:How to Slice a Bagel into Two Linked Halves (2009)
by delecti on Friday January 26, 2018 @04:25PM
(#16243027)
Not necessarily. Just as you could take a chain and stack the links such that the holes lined up, with enough precision, and a strong enough baked good, you could cut the bagel such that there were a chain of linked rings.
Re:How to Slice a Bagel into Two Linked Halves (2009)
by tritium on Friday January 26, 2018 @07:19PM
(#16244018)
Well, if you cut the bagel according to this particular linked torodial method, to produce two links, you’d then be able to perform the traditional bagel slice on one of the linked halves, and that would produce a chain with three links...
But deriving from a single original torus, a chain with an arbitrary or infinite number of links, whereby each individual link is bound to no more than two other links? I’ll have to think about that one...
Re:How to Slice a Bagel into Two Linked Halves (2009)
by tkahnoski on Friday January 26, 2018 @06:10PM
(#16243636)
Just had a brief discussion at work about bagels that started with a complaint about how they're never sliced all the way through.
After a couple minutes of back and forth an epiphany was realized that if they were pre-cut all the way through they'd get jumbled up and then we'd spend way too much time rifling through halves to find a matching one.
Re:How to Slice a Bagel into Two Linked Halves (2009)
by tzahola on Friday January 26, 2018 @05:01PM
(#16243247)
T-topologically w-what??
I mean yeah, that was the point of my remark.
To write something on topic as well:
There was a fun little challenge on puzzles.stackexchange I think, which relied on the same construction as this article. I couldn’t find it, but it went like this:
“You’re stuck on top of a tall building with nothing but a saw. There’s a ladder fastened to the side of the building, but it’s unfortunately not long enough to reach the ground; in fact it goes about half the height of the building from the top. Challenge is to get on the ground “safely”. You can cut into the ladder with your saw in any way you like and you can assume that the resulting pieces will be rigid, but won’t break under load.”
Re:How to Slice a Bagel into Two Linked Halves (2009)
by Retra on Saturday January 27, 2018 @12:20AM
(#16244976)
The problem is then you have two short ladders. You throw your two half ladders off the roof and they don't magically stand end-to-end for you. You have to cut with a twist to ensure the last rungs are entangled with each other so the half-ladders are hooked together. Then you can hang one off the other and reach the ground.
That family must have the best picnics!
[0] https://www.youtube.com/user/protopod
[1] https://www.youtube.com/watch?v=hSkT77010fE
To think about it another way, imagine if you took a mobius strip and constructed a semicircular lump of bread on the surface, extending it around until it connects back to itself. You've made a bagel!
Now take the mobius strip out of the middle, and the gap it leaves is the cut you're asking to make.
I wonder if I could sell bagel-sized silicone mobius strips for baking.
I'd suggest raising a few million in seed funding and renting an office in downtown SF. If it doesn't pan out you can pivot into math-related silicone ice cube trays.
However, I of course have no bagels or bagel accessories on the one day I read about mathematically correct bagels :(
So yeah, added to my grocery list too!
But deriving from a single original torus, a chain with an arbitrary or infinite number of links, whereby each individual link is bound to no more than two other links? I’ll have to think about that one...
After a couple minutes of back and forth an epiphany was realized that if they were pre-cut all the way through they'd get jumbled up and then we'd spend way too much time rifling through halves to find a matching one.
Either way, bravo!
https://en.wikipedia.org/wiki/Villarceau_circles
Someone please ask Professor Shewchuk (UC Berkeley) and Professor Demaine (MIT) to look at this! Perfect geometric problem for both of them.
I mean yeah, that was the point of my remark.
To write something on topic as well:
There was a fun little challenge on puzzles.stackexchange I think, which relied on the same construction as this article. I couldn’t find it, but it went like this:
“You’re stuck on top of a tall building with nothing but a saw. There’s a ladder fastened to the side of the building, but it’s unfortunately not long enough to reach the ground; in fact it goes about half the height of the building from the top. Challenge is to get on the ground “safely”. You can cut into the ladder with your saw in any way you like and you can assume that the resulting pieces will be rigid, but won’t break under load.”
Each rung would go from a cylinder to a half-cylinder, but should still be rigidly connected to either side of the ladder all the same.