FACTOID # 14: North Carolina has a larger Native American population than North Dakota, South Dakota and Montana combined.
 
 Home   Encyclopedia   Statistics   States A-Z   Flags   Maps   FAQ   About 
   
 
WHAT'S NEW
RELATED ARTICLES
People who viewed "Unknot" also viewed:
 

SEARCH ALL

FACTS & STATISTICS    Advanced view

Search encyclopedia, statistics and forums:

 

 

(* = Graphable)

 

 


Encyclopedia > Unknot
Enlarge
The unknot, and a knot equivalent to it

The unknot is a loop of rope without a knot in it (in knot theory, ropes have no ends; they are loops).


A knot theory might describe the unknot as the standard embedding of the circle (i.e. what the layman would call a circle), though any knot that can be 'untied' to give this would also be considered as the unknot. Deciding if a particular knot is the unknot was a major driving force behind knot invariants and it is not known whether the current invariants are sufficient to answer this question.


An unknow is the identity element with respect to the connected sum of knots operation.


This object is also called the not knot or the trivial knot. The latter is the more natural name for it, since it fits in with the usual mathematical concept of 'trivial', but the punning term unknot has stuck. Nevertheless, it is common to say a knot 'is trivial' to mean it is the unknot.


Some useful rope shapes are actually unknots, such as the slip knot and the sheepshank.


See also:

  • Knot (mathematics)

  Results from FactBites:
 
PlanetMath: unknot (66 words)
The unknot is the knot with a projection containing no crossings, or equivalently the knot with three vertices.
This is version 3 of unknot, born on 2002-12-19, modified 2002-12-20.
Object id is 3777, canonical name is Unknot.
Definition of unknot - Merriam-Webster Online Dictionary (38 words)
Learn more about "unknot" and related topics at Britannica.com
Find more about "unknot" instantly with Live Search
See a map of "unknot" in the Visual Thesaurus
  More results at FactBites »

 
 

COMMENTARY     


Share your thoughts, questions and commentary here
Your name
Your comments

Want to know more?
Search encyclopedia, statistics and forums:

 


Press Releases |  Feeds | Contact
The Wikipedia article included on this page is licensed under the GFDL.
Images may be subject to relevant owners' copyright.
All other elements are (c) copyright NationMaster.com 2003-5. All Rights Reserved.
Usage implies agreement with terms, 1022, m