6 2
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Visit 6 2's page at the Knot Server (KnotPlot driven, includes 3D interactive images!)
Visit 6 2's page at Knotilus! Visit 6 2's page at the original Knot Atlas! |
Dror likes to call 6_2 "The Miller Institute Knot", as it is the logo of the Miller Institute for Basic Research.
The bowline knot of practical knot tying deforms to 6_2. |
Knot presentations
Planar diagram presentation | X1425 X5,10,6,11 X3948 X9,3,10,2 X7,12,8,1 X11,6,12,7 |
Gauss code | -1, 4, -3, 1, -2, 6, -5, 3, -4, 2, -6, 5 |
Dowker-Thistlethwaite code | 4 8 10 12 2 6 |
Conway Notation | [312] |
Three dimensional invariants
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Four dimensional invariants
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Polynomial invariants
A1 Invariants.
Weight | Invariant |
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1 | |
2 | |
3 | |
4 | |
5 | |
6 |
A2 Invariants.
Weight | Invariant |
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1,0 | |
1,1 | |
2,0 | |
3,0 |
A3 Invariants.
Weight | Invariant |
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0,1,0 | |
1,0,0 | |
1,0,1 |
A4 Invariants.
Weight | Invariant |
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0,1,0,0 | |
1,0,0,0 |
B2 Invariants.
Weight | Invariant |
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0,1 | |
1,0 |
D4 Invariants.
Weight | Invariant |
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1,0,0,0 |
G2 Invariants.
Weight | Invariant |
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1,0 |
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KnotTheory`
, as shown in the (simulated) Mathematica session below. Your input (in red) is realistic; all else should have the same content as in a real mathematica session, but with different formatting. This Mathematica session is also available (albeit only for the knot 5_2) as the notebook PolynomialInvariantsSession.nb.
(The path below may be different on your system, and possibly also the KnotTheory` date)
In[1]:=
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AppendTo[$Path, "C:/drorbn/projects/KAtlas/"];
<< KnotTheory`
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Loading KnotTheory` version of August 31, 2006, 11:25:27.5625.
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In[3]:=
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K = Knot["6 2"];
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In[4]:=
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Alexander[K][t]
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KnotTheory::loading: Loading precomputed data in PD4Knots`.
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Out[4]=
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In[5]:=
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Conway[K][z]
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Out[5]=
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In[6]:=
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Alexander[K, 2][t]
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KnotTheory::credits: The program Alexander[K, r] to compute Alexander ideals was written by Jana Archibald at the University of Toronto in the summer of 2005.
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Out[6]=
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In[7]:=
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{KnotDet[K], KnotSignature[K]}
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Out[7]=
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{ 11, -2 } |
In[8]:=
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Jones[K][q]
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KnotTheory::loading: Loading precomputed data in Jones4Knots`.
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Out[8]=
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In[9]:=
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HOMFLYPT[K][a, z]
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KnotTheory::credits: The HOMFLYPT program was written by Scott Morrison.
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Out[9]=
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In[10]:=
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Kauffman[K][a, z]
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KnotTheory::loading: Loading precomputed data in Kauffman4Knots`.
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Out[10]=
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Vassiliev invariants
V2 and V3: | (-1, 1) |
V2,1 through V6,9: |
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V2,1 through V6,9 were provided by Petr Dunin-Barkowski <barkovs@itep.ru>, Andrey Smirnov <asmirnov@itep.ru>, and Alexei Sleptsov <sleptsov@itep.ru> and uploaded on October 2010 by User:Drorbn. Note that they are normalized differently than V2 and V3.
Khovanov Homology
The coefficients of the monomials are shown, along with their alternating sums (fixed , alternation over ). The squares with yellow highlighting are those on the "critical diagonals", where or , where -2 is the signature of 6 2. Nonzero entries off the critical diagonals (if any exist) are highlighted in red.
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-4 | -3 | -2 | -1 | 0 | 1 | 2 | χ | |||||||||
3 | 1 | 1 | |||||||||||||||
1 | 0 | ||||||||||||||||
-1 | 2 | 1 | 1 | ||||||||||||||
-3 | 1 | 1 | 0 | ||||||||||||||
-5 | 1 | 1 | 0 | ||||||||||||||
-7 | 1 | 1 | 0 | ||||||||||||||
-9 | 1 | -1 | |||||||||||||||
-11 | 1 | 1 |
Computer Talk
Much of the above data can be recomputed by Mathematica using the package KnotTheory`
. See A Sample KnotTheory` Session.
In[1]:= |
<< KnotTheory` |
Loading KnotTheory` (version of August 17, 2005, 14:44:34)... | |
In[2]:= | Crossings[Knot[6, 2]] |
Out[2]= | 6 |
In[3]:= | PD[Knot[6, 2]] |
Out[3]= | PD[X[1, 4, 2, 5], X[5, 10, 6, 11], X[3, 9, 4, 8], X[9, 3, 10, 2], X[7, 12, 8, 1], X[11, 6, 12, 7]] |
In[4]:= | GaussCode[Knot[6, 2]] |
Out[4]= | GaussCode[-1, 4, -3, 1, -2, 6, -5, 3, -4, 2, -6, 5] |
In[5]:= | BR[Knot[6, 2]] |
Out[5]= | BR[3, {-1, -1, -1, 2, -1, 2}] |
In[6]:= | alex = Alexander[Knot[6, 2]][t] |
Out[6]= | -2 3 2 |
In[7]:= | Conway[Knot[6, 2]][z] |
Out[7]= | 2 4 1 - z - z |
In[8]:= | Select[AllKnots[], (alex === Alexander[#][t])&] |
Out[8]= | {Knot[6, 2]} |
In[9]:= | {KnotDet[Knot[6, 2]], KnotSignature[Knot[6, 2]]} |
Out[9]= | {11, -2} |
In[10]:= | J=Jones[Knot[6, 2]][q] |
Out[10]= | -5 2 2 2 2 |
In[11]:= | Select[AllKnots[], (J === Jones[#][q] || (J /. q-> 1/q) === Jones[#][q])&] |
Out[11]= | {Knot[6, 2]} |
In[12]:= | A2Invariant[Knot[6, 2]][q] |
Out[12]= | -16 -8 -4 -2 2 4 1 + q - q - q + q + q + q |
In[13]:= | Kauffman[Knot[6, 2]][a, z] |
Out[13]= | 2 4 3 5 2 2 2 4 2 6 2 |
In[14]:= | {Vassiliev[2][Knot[6, 2]], Vassiliev[3][Knot[6, 2]]} |
Out[14]= | {0, 1} |
In[15]:= | Kh[Knot[6, 2]][q, t] |
Out[15]= | -3 2 1 1 1 1 1 1 1 t |