# Moebius strip

In

HW 9 was asked to build a Möbius strip.
It is a well known trick to cut a Moebius strip into two. The result is a new strip
but as it is a double cover of the old one, one gets an oriented surface. What happens
if one cuts it again along the middle line? A bit surprisingly, one ends up with two
interlinked strips. Grace, one of the students in this multivariable course experimented
as such (see the picture).

It is
a known thing but still a bit surprising. Topologically, the once cut strip is an
orientable surface which an annulus (a finite cylinder).
If one looks at an annulus and cuts it into
two, then one ends up with two disjoint annuli which are not linked. It is the twisting
which has made the two parts interlinked. If cutting each again, then one ends up with
4 interlinked bands.
The Moebius strip appewared in the

recent
Avengers End game movie.