หัวข้อ: Knot theory
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Old 19 ธันวาคม 2020, 13:57
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Knot theory, in mathematics, the study of closed curves in three dimensions,
and their possible deformations without one part cutting through another.

Knots may be regarded as formed by interlacing and looping a piece of string
in any fashion and then joining the ends.

The first question that arises is whether such a curve is truly knotted or
can simply be untangled; that is, whether or not
one can deform it in space into a standard unknotted curve like a circle.

The second question is whether, more generally,
any two given curves represent different knots or are really the same knot
in the sense that one can be continuously deformed into the other.


https://www.britannica.com/science/knot-theory
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