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cohomology theory

Hans Aberg Jan 14, 1999 12:00 AM
Posted in group: sci.physics.research
In article <76r4a6$nlr$>, (john baez) wrote:
>Don't get mixed up by the difference between topology and geometry.  Alas,
>it's probably hopeless discussing this without me actually looking at that
>stocking.  Some things just don't work well in writing.  If you tried to
>explain *in writing* how you tie your shoelaces, for me to understand it
>would be a major intellectual feat, worthy of an Einstein.  It's probably
>best to save both our brain cells for something a bit more useful.

Speaking about tying your shoelaces, I and some friend was able to develop
an interestiong thoery why some tie good knots and other don't. Perhaps
some physicist can give the full theoretical explanation:

If one carefully pulls in the shoelace loops of the tied shoelace knots
out so that the result is a knot (instead of untying the shoelaces), then
there are two variations that can occur, the reef-knot and the granny's
knot. The former shoelace knot will hold well, but the other will not.

So here is an explanation why every second ties a good shoelace knot and
every second generation ties bad one: When mom teaches the child to tie
the knot, she stands in front of the child; the child first ties the
simple crossing of laces, but when mom shows the child doing the
complicated shoelace knot loops, the child is taught the mirror reversed
variation. So every second generation it switches between a reef-knot and
a granny's knot.

>(By the way, I've read that Einstein didn't wear socks, and he once
>painted his toes black to camouflage some holes in his shoes.  The man
>was obviously a genius.  But I digress....)

I have not tried this; it probably generalizes to covering up holes in
socks as well. But a mathematican would probably prefer to use cohomology
theory. (As in an earlier article in this thread, where cohomology was
likened with studying the behavior around holes, and socks with holes were
likened topological surfaces with holes.)

  Hans Aberg   * Anti-spam: Remove "REMOVE." from email address.
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