In
mathematics, a stuck unknot is a closed
polygonal chain that is topologically equal to the
unknot but cannot be deformed to a
simple polygon by rigid motions of the segments.
[G. T. Toussaint, "A new class of stuck unknots in Pol-6," ''Contributions to Algebra and Geometry'', Vol. 42, No. 2, 2001, pp. 301–306.]
Similarly a stuck open chain is an open polygonal chain such that the segments may not be aligned by moving rigidly its segments. Topologically such a chain can be unknotted, but the limitation of using only rigid motions of the segments can create
nontrivial knots in such a chain.
Consideration of such "stuck" configurations arises in the study of
molecular chains in
biochemistry
Biochemistry or biological chemistry is the study of chemical processes within and relating to living organisms. A sub-discipline of both chemistry and biology, biochemistry may be divided into three fields: structural biology, enzymology ...
.
References
Knots (knot theory)
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