2. It is a topological structure with only one surface and one boundary. It was created by the German mathematician and astronomer Auguste Ferdinand M? Bius) and John Christine (John? Benedict list) was independently discovered on 1858. This structure can be easily made by rotating a paper tape for half a turn and then gluing the two ends together. In fact, there are two different Mobius tape images, which are symmetrical to each other. If the paper tape is rotated clockwise and then pasted, a right-handed Mobius tape will be formed, and vice versa.
3. Mobius ring and Klein bottle can be compared:
Mobius ring shows an endless two-dimensional plane in a certain direction. If you are a two-dimensional person and live on a Mobius ring, from the perspective of three-dimensional space, you will always circle on both sides of the Mobius ring. Because you are a second-dimensional person, you must be in the dark, and you will not feel the reversal of the positive and negative sides, thinking that the world is like this and there is no end.
Similarly,
Klein bottle presents endless three-dimensional space in a certain direction. If you are a three-dimensional person (as we are now) and live in a Klein bottle, from the perspective of four-dimensional space, you will always shuttle between the two spaces of the Klein bottle. Because you are a three-dimensional person, you must be in the dark, and you won't feel ... thinking that the world is like this, with no end.