
How one-sided objects like a Mobius strip work - happy-go-lucky
http://www.bbc.com/future/story/20181026-how-one-sided-objects-like-a-mobius-strip-work
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ocfnash
This was news to me and pretty striking:

> The concept of orientability has important implications. Take enantiomers.
> These chemical compounds have the same chemical structures except for one
> key difference: they are mirror images of one another. For example, the
> chemical L-methamphetamine is an ingredient in Vicks inhalers. Its mirror
> image, D-methamphetamine, is a Class A illegal drug. If we lived in a
> nonorientable world, these chemicals would be indistinguishable.

~~~
tome
> If we lived in a nonorientable world, these chemicals would be
> indistinguishable.

True, but you might have to move such a molecule arbitrarily far ("all the way
around the Mobius strip") in order to change it from one enantiomer to ther
other.

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jeppz
Wait, am I crazy or is that metal strip actually not a Mobius?

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trampi
as far as I can tell: no, it does not seem to be a Mobius.

Edit: They did change the image. In the last image, they showed a metal
surface which wrapped two times and had not the properties of a mobius strip.

Edit 2: found it, the old image was this stock image:
[https://www.istockphoto.com/de/foto/moebius-streifen-in-
meta...](https://www.istockphoto.com/de/foto/moebius-streifen-in-metallic-
optik-gm501799768-81548797)

~~~
coldtea
> _Edit: They did change the image. In the last image, they showed a metal
> surface which wrapped two times and had not the properties of a mobius
> strip._

This is still a single-sided surface though (with the 2 twists).

Wikipedia: "the Möbius strip can also be formed by twisting the strip an odd
number of times greater than one"

Not sure about needing to be "odd", I think 2 qualifies as well, so perhaps
odd or even AND prime does it...

~~~
jackcarter
No, it has two sides. Pick a side and trace it with your finger - you'll never
get to the other side.

(I'm talking about this image, from the second edit:
[https://www.istockphoto.com/de/foto/moebius-streifen-in-
meta...](https://www.istockphoto.com/de/foto/moebius-streifen-in-metallic-
optik-gm501799768-81548797) )

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foreigner
I love these. Imagine a giant Mobius strip. Cut a hole in it and install a
doorway. When you walk through that doorway where do you go? Not to the other
side because THERE IS NO OTHER SIDE!

Personally I think you enter an alternate universe. Just thinking about it
makes my brain dribble out of my ears.

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v_lisivka
Why not use sphere instead? It has no "sides" at all by your definition of
"side".

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informatimago
A sphere has two sIdes: an internal side, and an external side. This is why
there are theories of “hollow earth”!

~~~
fabricexpert
huh? that would not be a sphere. A sphere has no internal sides it's solid all
the way through

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tomstuart
For what it’s worth, mathematically a “sphere” is the set of all points which
are equidistant from its centre — it’s _hollow_ all the way through. The solid
version is called a “ball”.

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tw1010
Funny how skimming messes with how you read things. You kind of read things in
pieces, at almost a random order, and then your brain tries to interpolate the
missing pieces (sometimes successfully, sometimes not). When I first read this
title I just picked up "Mobius strip" and "work", and thought (in an half-
baked way) it'd be an article about how some kind of mobius strip-inspired
scheduling pattern could make for a more improved working style.

Although this malfunctioning reading mechanism is often a cause for confusion,
sometimes it's also an interesting source of creativity and weird ideas.

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burfog
Fucking _magnetic monopoles_ , how do they work?

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samwhiteUK
Ho can a coffee cup be transformed into a doughnut? is the "hole" they are
referring to the handle?

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mnw21cam
Is it disturbing that when I read "coffee cup", I thought of those paper
disposable things with no handle?

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msla
> Is it disturbing that when I read "coffee cup", I thought of those paper
> disposable things with no handle?

No, because the usual term for the ceramic thing with the handle is a coffee
mug.

