8 16: Difference between revisions

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{{Rolfsen Knot Page Header|n=8|k=16|KnotilusURL=http://srankin.math.uwo.ca/cgi-bin/retrieve.cgi/1,-8,5,-6,2,-1,4,-5,6,-7,3,-4,8,-2,7,-3/goTop.html}}
{| align=left
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|{{Rolfsen Knot Site Links|n=8|k=16|KnotilusURL=http://srankin.math.uwo.ca/cgi-bin/retrieve.cgi/1,-8,5,-6,2,-1,4,-5,6,-7,3,-4,8,-2,7,-3/goTop.html}}
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{{Vassiliev Invariants}}
{{Vassiliev Invariants}}


===[[Khovanov Homology]]===
{{Khovanov Homology|table=<table border=1>

The coefficients of the monomials <math>t^rq^j</math> are shown, along with their alternating sums <math>\chi</math> (fixed <math>j</math>, alternation over <math>r</math>). The squares with <font class=HLYellow>yellow</font> highlighting are those on the "critical diagonals", where <math>j-2r=s+1</math> or <math>j-2r=s+1</math>, where <math>s=</math>{{Data:{{PAGENAME}}/Signature}} is the signature of {{PAGENAME}}. Nonzero entries off the critical diagonals (if any exist) are highlighted in <font class=HLRed>red</font>.

<center><table border=1>
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<tr align=center>
<td width=15.3846%><table cellpadding=0 cellspacing=0>
<td width=15.3846%><table cellpadding=0 cellspacing=0>
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<tr align=center><td>-11</td><td bgcolor=yellow>&nbsp;</td><td bgcolor=yellow>2</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>2</td></tr>
<tr align=center><td>-11</td><td bgcolor=yellow>&nbsp;</td><td bgcolor=yellow>2</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>2</td></tr>
<tr align=center><td>-13</td><td bgcolor=yellow>1</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>-1</td></tr>
<tr align=center><td>-13</td><td bgcolor=yellow>1</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>-1</td></tr>
</table></center>
</table>}}

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{{Computer Talk Header}}


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q t q t</nowiki></pre></td></tr>
q t q t</nowiki></pre></td></tr>
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[[Category:Knot Page]]

Revision as of 20:12, 28 August 2005

8 15.gif

8_15

8 17.gif

8_17

8 16.gif Visit 8 16's page at the Knot Server (KnotPlot driven, includes 3D interactive images!)

Visit 8 16's page at Knotilus!

Visit 8 16's page at the original Knot Atlas!

8 16 Quick Notes



Square depiction.

Knot presentations

Planar diagram presentation X6271 X14,6,15,5 X16,11,1,12 X12,7,13,8 X8394 X4,9,5,10 X10,15,11,16 X2,14,3,13
Gauss code 1, -8, 5, -6, 2, -1, 4, -5, 6, -7, 3, -4, 8, -2, 7, -3
Dowker-Thistlethwaite code 6 8 14 12 4 16 2 10
Conway Notation [.2.20]

Three dimensional invariants

Symmetry type Reversible
Unknotting number 2
3-genus 3
Bridge index 3
Super bridge index 4
Nakanishi index 1
Maximal Thurston-Bennequin number [-8][-2]
Hyperbolic Volume 10.579
A-Polynomial See Data:8 16/A-polynomial

[edit Notes for 8 16's three dimensional invariants]

Four dimensional invariants

Smooth 4 genus [math]\displaystyle{ 1 }[/math]
Topological 4 genus [math]\displaystyle{ 1 }[/math]
Concordance genus [math]\displaystyle{ 3 }[/math]
Rasmussen s-Invariant 2

[edit Notes for 8 16's four dimensional invariants]

Polynomial invariants

Alexander polynomial [math]\displaystyle{ t^3-4 t^2+8 t-9+8 t^{-1} -4 t^{-2} + t^{-3} }[/math]
Conway polynomial [math]\displaystyle{ z^6+2 z^4+z^2+1 }[/math]
2nd Alexander ideal (db, data sources) [math]\displaystyle{ \{1\} }[/math]
Determinant and Signature { 35, -2 }
Jones polynomial [math]\displaystyle{ -q^2+3 q-4+6 q^{-1} -6 q^{-2} +6 q^{-3} -5 q^{-4} +3 q^{-5} - q^{-6} }[/math]
HOMFLY-PT polynomial (db, data sources) [math]\displaystyle{ a^2 z^6-a^4 z^4+4 a^2 z^4-z^4-2 a^4 z^2+5 a^2 z^2-2 z^2-a^4+2 a^2 }[/math]
Kauffman polynomial (db, data sources) [math]\displaystyle{ z^3 a^7+3 z^4 a^6-z^2 a^6+5 z^5 a^5-5 z^3 a^5+2 z a^5+5 z^6 a^4-7 z^4 a^4+4 z^2 a^4-a^4+2 z^7 a^3+3 z^5 a^3-10 z^3 a^3+4 z a^3+8 z^6 a^2-18 z^4 a^2+10 z^2 a^2-2 a^2+2 z^7 a-z^5 a-6 z^3 a+3 z a+3 z^6-8 z^4+5 z^2+z^5 a^{-1} -2 z^3 a^{-1} +z a^{-1} }[/math]
The A2 invariant [math]\displaystyle{ -q^{18}+q^{16}-q^{14}+q^{10}-q^8+2 q^6-q^4+2 q^2+1+ q^{-4} - q^{-6} }[/math]
The G2 invariant [math]\displaystyle{ q^{100}-2 q^{98}+3 q^{96}-4 q^{94}+2 q^{92}-q^{90}-2 q^{88}+9 q^{86}-12 q^{84}+15 q^{82}-14 q^{80}+7 q^{78}+2 q^{76}-16 q^{74}+28 q^{72}-31 q^{70}+24 q^{68}-10 q^{66}-11 q^{64}+26 q^{62}-30 q^{60}+21 q^{58}-5 q^{56}-15 q^{54}+23 q^{52}-19 q^{50}+2 q^{48}+22 q^{46}-36 q^{44}+36 q^{42}-20 q^{40}-4 q^{38}+30 q^{36}-45 q^{34}+46 q^{32}-33 q^{30}+12 q^{28}+14 q^{26}-32 q^{24}+39 q^{22}-30 q^{20}+14 q^{18}+5 q^{16}-20 q^{14}+24 q^{12}-14 q^{10}-q^8+21 q^6-29 q^4+26 q^2-6-17 q^{-2} +35 q^{-4} -37 q^{-6} +28 q^{-8} -10 q^{-10} -12 q^{-12} +24 q^{-14} -25 q^{-16} +20 q^{-18} -9 q^{-20} -2 q^{-22} +6 q^{-24} -8 q^{-26} +5 q^{-28} -2 q^{-30} + q^{-32} }[/math]

Vassiliev invariants

V2 and V3: (1, -1)
V2,1 through V6,9:
V2,1 V3,1 V4,1 V4,2 V4,3 V5,1 V5,2 V5,3 V5,4 V6,1 V6,2 V6,3 V6,4 V6,5 V6,6 V6,7 V6,8 V6,9
[math]\displaystyle{ 4 }[/math] [math]\displaystyle{ -8 }[/math] [math]\displaystyle{ 8 }[/math] [math]\displaystyle{ \frac{14}{3} }[/math] [math]\displaystyle{ -\frac{38}{3} }[/math] [math]\displaystyle{ -32 }[/math] [math]\displaystyle{ -\frac{80}{3} }[/math] [math]\displaystyle{ \frac{64}{3} }[/math] [math]\displaystyle{ -8 }[/math] [math]\displaystyle{ \frac{32}{3} }[/math] [math]\displaystyle{ 32 }[/math] [math]\displaystyle{ \frac{56}{3} }[/math] [math]\displaystyle{ -\frac{152}{3} }[/math] [math]\displaystyle{ \frac{1951}{30} }[/math] [math]\displaystyle{ -\frac{114}{5} }[/math] [math]\displaystyle{ -\frac{298}{45} }[/math] [math]\displaystyle{ -\frac{31}{18} }[/math] [math]\displaystyle{ -\frac{449}{30} }[/math]

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 [math]\displaystyle{ t^rq^j }[/math] are shown, along with their alternating sums [math]\displaystyle{ \chi }[/math] (fixed [math]\displaystyle{ j }[/math], alternation over [math]\displaystyle{ r }[/math]). The squares with yellow highlighting are those on the "critical diagonals", where [math]\displaystyle{ j-2r=s+1 }[/math] or [math]\displaystyle{ j-2r=s-1 }[/math], where [math]\displaystyle{ s= }[/math]-2 is the signature of 8 16. Nonzero entries off the critical diagonals (if any exist) are highlighted in red.   
\ r
  \  
j \
-5-4-3-2-10123χ
5        1-1
3       2 2
1      21 -1
-1     42  2
-3    33   0
-5   33    0
-7  23     1
-9 13      -2
-11 2       2
-131        -1
Integral Khovanov Homology

(db, data source)

  
[math]\displaystyle{ \dim{\mathcal G}_{2r+i}\operatorname{KH}^r_{\mathbb Z} }[/math] [math]\displaystyle{ i=-3 }[/math] [math]\displaystyle{ i=-1 }[/math]
[math]\displaystyle{ r=-5 }[/math] [math]\displaystyle{ {\mathbb Z} }[/math]
[math]\displaystyle{ r=-4 }[/math] [math]\displaystyle{ {\mathbb Z}^{2}\oplus{\mathbb Z}_2 }[/math] [math]\displaystyle{ {\mathbb Z} }[/math]
[math]\displaystyle{ r=-3 }[/math] [math]\displaystyle{ {\mathbb Z}^{3}\oplus{\mathbb Z}_2^{2} }[/math] [math]\displaystyle{ {\mathbb Z}^{2} }[/math]
[math]\displaystyle{ r=-2 }[/math] [math]\displaystyle{ {\mathbb Z}^{3}\oplus{\mathbb Z}_2^{3} }[/math] [math]\displaystyle{ {\mathbb Z}^{3} }[/math]
[math]\displaystyle{ r=-1 }[/math] [math]\displaystyle{ {\mathbb Z}^{3}\oplus{\mathbb Z}_2^{3} }[/math] [math]\displaystyle{ {\mathbb Z}^{3} }[/math]
[math]\displaystyle{ r=0 }[/math] [math]\displaystyle{ {\mathbb Z}^{3}\oplus{\mathbb Z}_2^{3} }[/math] [math]\displaystyle{ {\mathbb Z}^{4} }[/math]
[math]\displaystyle{ r=1 }[/math] [math]\displaystyle{ {\mathbb Z}^{2}\oplus{\mathbb Z}_2^{2} }[/math] [math]\displaystyle{ {\mathbb Z}^{2} }[/math]
[math]\displaystyle{ r=2 }[/math] [math]\displaystyle{ {\mathbb Z}\oplus{\mathbb Z}_2^{2} }[/math] [math]\displaystyle{ {\mathbb Z}^{2} }[/math]
[math]\displaystyle{ r=3 }[/math] [math]\displaystyle{ {\mathbb Z}_2 }[/math] [math]\displaystyle{ {\mathbb Z} }[/math]

Computer Talk

Much of the above data can be recomputed by Mathematica using the package KnotTheory`. See A Sample KnotTheory` Session.

[math]\displaystyle{ \textrm{Include}(\textrm{ColouredJonesM.mhtml}) }[/math]

In[1]:=    
<< KnotTheory`
Loading KnotTheory` (version of August 17, 2005, 14:44:34)...
In[2]:=
Crossings[Knot[8, 16]]
Out[2]=  
8
In[3]:=
PD[Knot[8, 16]]
Out[3]=  
PD[X[6, 2, 7, 1], X[14, 6, 15, 5], X[16, 11, 1, 12], X[12, 7, 13, 8], 
  X[8, 3, 9, 4], X[4, 9, 5, 10], X[10, 15, 11, 16], X[2, 14, 3, 13]]
In[4]:=
GaussCode[Knot[8, 16]]
Out[4]=  
GaussCode[1, -8, 5, -6, 2, -1, 4, -5, 6, -7, 3, -4, 8, -2, 7, -3]
In[5]:=
BR[Knot[8, 16]]
Out[5]=  
BR[3, {-1, -1, 2, -1, -1, 2, -1, 2}]
In[6]:=
alex = Alexander[Knot[8, 16]][t]
Out[6]=  
      -3   4    8            2    3

-9 + t - -- + - + 8 t - 4 t + t

           2   t
t
In[7]:=
Conway[Knot[8, 16]][z]
Out[7]=  
     2      4    6
1 + z  + 2 z  + z
In[8]:=
Select[AllKnots[], (alex === Alexander[#][t])&]
Out[8]=  
{Knot[8, 16], Knot[10, 156], Knot[11, NonAlternating, 15], 
  Knot[11, NonAlternating, 56], Knot[11, NonAlternating, 58]}
In[9]:=
{KnotDet[Knot[8, 16]], KnotSignature[Knot[8, 16]]}
Out[9]=  
{35, -2}
In[10]:=
J=Jones[Knot[8, 16]][q]
Out[10]=  
      -6   3    5    6    6    6          2

-4 - q + -- - -- + -- - -- + - + 3 q - q

           5    4    3    2   q
q q q q
In[11]:=
Select[AllKnots[], (J === Jones[#][q] || (J /. q-> 1/q) === Jones[#][q])&]
Out[11]=  
{Knot[8, 16], Knot[10, 156]}
In[12]:=
A2Invariant[Knot[8, 16]][q]
Out[12]=  
     -18    -16    -14    -10    -8   2     -4   2     4    6

1 - q + q - q + q - q + -- - q + -- + q - q

                                      6          2
q q
In[13]:=
Kauffman[Knot[8, 16]][a, z]
Out[13]=  
    2    4   z              3        5        2       2  2      4  2

-2 a - a + - + 3 a z + 4 a z + 2 a z + 5 z + 10 a z + 4 a z -

            a

            3
  6  2   2 z         3       3  3      5  3    7  3      4
 a  z  - ---- - 6 a z  - 10 a  z  - 5 a  z  + a  z  - 8 z  - 
          a

                                 5
     2  4      4  4      6  4   z       5      3  5      5  5      6
 18 a  z  - 7 a  z  + 3 a  z  + -- - a z  + 3 a  z  + 5 a  z  + 3 z  + 
                                a

    2  6      4  6        7      3  7
8 a z + 5 a z + 2 a z + 2 a z
In[14]:=
{Vassiliev[2][Knot[8, 16]], Vassiliev[3][Knot[8, 16]]}
Out[14]=  
{0, -1}
In[15]:=
Kh[Knot[8, 16]][q, t]
Out[15]=  
3    4     1        2        1       3       2       3       3

-- + - + ------ + ------ + ----- + ----- + ----- + ----- + ----- +

3   q    13  5    11  4    9  4    9  3    7  3    7  2    5  2

q q t q t q t q t q t q t q t

  3      3     2 t              2      3  2    5  3
 ---- + ---- + --- + 2 q t + q t  + 2 q  t  + q  t
  5      3      q
q t q t