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The man with 1,000 klein bottles under his house [video]

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Re: The man with 1,000 klein bottles under his house [video]

#11
This is incredible. I LOVE stuff like this. It makes me so happy that people like this still exist in the world. I say 'still' because I feel like they're a dying breed. The rationale behind everything he's done is laid bare and it makes sense! People like this don't ever let a detail like "I have no idea how to achieve this" stand in their way. Everything is a challenge or problem that needs solving.

Re: The man with 1,000 klein bottles under his house [video]

#12
post #7

Cliff Stoll in case people were wondering: https://en.wikipedia.org/wiki/Clifford_Stoll I have his original book my shelf, it was fascinating when it came out. His Klein Bottle company is here: http://www.kleinbottle.com/

Oh my god the Cuckoo's Egg guy! That is a crazy book. Would never have connected them, but then again clearly this is someone who doesn't let go once he gets an idea between his teeth.

It was interesting to read the Cyberpunk by John Markoff after the Cockoo's egg, because this book covered the same case from the crackers point of view.

Re: The man with 1,000 klein bottles under his house [video]

#13
post #8
post #5

Real life Gyro Gearloose!!! In the next video he talks about how a Klein bottle is made, and how, contrary to a bottle, it has no edge. I'm not sure I understand why a bottle "has to" have an edge? Surely it's possible to make a bottle with no edge? For example, if one takes a sphere and progressively turns it into a bowl (by punching into it), and then makes the bowl deeper, it still has just one surface and no edge…

If you make this bowl, it will have two surfaces, with no way to get from one side to the other.

Well, I'm not sure about that. The top of my bowl is the top-half of a doughnut if you will: it really does not seem to have an edge. At what point does an "edge" appear?

Re: The man with 1,000 klein bottles under his house [video]

#15
post #13
post #8

Earlier quoted context omitted.

If you make this bowl, it will have two surfaces, with no way to get from one side to the other.

Well, I'm not sure about that. The top of my bowl is the top-half of a doughnut if you will: it really does not seem to have an edge. At what point does an "edge" appear?

But you do have two surfaces: inside and outside. The Klein bottle only has one.

Re: The man with 1,000 klein bottles under his house [video]

#16
post #13
post #8

Earlier quoted context omitted.

If you make this bowl, it will have two surfaces, with no way to get from one side to the other.

Well, I'm not sure about that. The top of my bowl is the top-half of a doughnut if you will: it really does not seem to have an edge. At what point does an "edge" appear?

It has an inner surface and an outer surface, the same as a sphere. They didn't say it had an edge.

Re: The man with 1,000 klein bottles under his house [video]

#18
post #16
post #13

Earlier quoted context omitted.

Well, I'm not sure about that. The top of my bowl is the top-half of a doughnut if you will: it really does not seem to have an edge. At what point does an "edge" appear?

It has an inner surface and an outer surface, the same as a sphere. They didn't say it had an edge.

Yes, in the video I'm talking about https://www.youtube.com/watch?v=AAsICMPwGPY

he says that a bootle has an edge (~3'40).

A sphere does not have an "inner surface", it has just one surface. So does a potato. If you go from sphere to potato to bowl, when does an edge appear and does it have to appear, is my question.

Re: The man with 1,000 klein bottles under his house [video]

#20
post #18
post #16

Earlier quoted context omitted.

It has an inner surface and an outer surface, the same as a sphere. They didn't say it had an edge.

Yes, in the video I'm talking about https://www.youtube.com/watch?v=AAsICMPwGPY he says that a bootle has an edge (~3'40). A sphere does not have an "inner surface", it has just one surface. So does a potato. If you go from sphere to potato to bowl, when does an edge appear and does it have to appear, is my question.

Well. A bottle is topologically equivalent to a solid sphere. It only has one surface.

The inside and outside of a bottle is just by convention. Usually you would say something is inside the bottle if it is past the opening. (As he says in the video.)

So your example with the bowl-shaped "sphere" is correct. There's no clear limit when a bottle has an inside and an outside.

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