Knot diagrams
- n
a punctured sphere
as
a model
- f
string figures
434
'is E¥u U
l # KEEFE )
YEH # #t¥¥ A
l '¥k¥E¥i¥E¥I k¥3 )
(
Y
D Th Aa ITT
'
) YEH # #t A ( Th Aa ITT ' D Y = $2 R2 IR ' v - . . i - - PowerPoint PPT Presentation
a punctured sphere Knot diagrams on string figures of a model as l # KEEFE ) ' is Eu U 434 l 'kEiEI k3 ) ) YEH # #t A ( Th Aa ITT ' D Y = $2 R2 IR ' v - . . i diagram of K DE $2 knot KE $3 : :
Knot diagrams
a punctured sphere
as
a model
string figures
434
'is E¥u U
l # KEEFE )
YEH # #t¥¥ A
l '¥k¥E¥i¥E¥I k¥3 )
(
Y
D Th Aa ITT
'R2 → IR
'
v - = $2.
. → §
KE $3
:
knot
DE $2
i diagram of K
P
= PID ): underlying projection of D
N ( P)
i regular neighbourhood ofP
in $2
⑦ K E $3
= IR' un
t
'
' Q
R
{R I R is
a component of $ ' l N ( P))
( ( D )
: the number ofcrossings of
D
SER
,FIS )
511¥13
E
''
D
c ( D )
c ( K )
CCD , s ) : -_
min { ECE ) /EFD}
( ( D )
Exc
thm-CCD.pe/=Cl
First proved
by Keiji Taga mi (National Fisheries University)
.Thm2_
y :$
' → $2 : genericimmersion
@ Turaevcobracket ( arranged for
F
: oriented surfaceH
: = { y :$ ' → FI 9 : generic immersion
,get}H
: = HI = , (9) :ye
u
no
.:* . .⇒
9 ";Y y
l
y
F
) (
x
F
A
*
I
i H
→
2 ( H x H )
Tura ev
cobracketU
[ Y ] → pff ,y,
(( ( Yp ,
, ] ,C Yp , z))
y
TP, 2
Yp ,
iC (9)
i = the set of crossingsD l 9)
i = { PE C 19 )
/ Yp. , ¥0 , 9pm to}ftp.3-isawe/l-definedhomotopyinvarian-
)
A
→
) 0=0
g- in
"
""
.
%
. .y ( [ Yp , , ] , [ Bp , z ) )
t
( C Yoo
. ,] , [9g .D)=
O
9131
JI
5C
a
y
vg'
Sgp,z
Too
. ,y
( [ Yp , , ] , [ 9pm ] )
1-
( [ Yq
. ,] ,g.D)
=
O
Piq, q ,
[ Yp,,j]=[ 48;
>I]p#pz
2=1.23
,5=1,2
Y
Y
E
I4%1
x K
Yp, ,2 481,2
¢
n
X H )
→
Z E o
n f a , CK
i , Z , ) ta k ( Xh
. 2h )) : =I a , I t
I ah I
Prop.si
y :$
' → $2 : genericimmersion
,in;;aaerize
41$
' )"
Zhi yun
Cheng informed
usthat
is
an
immediate
consequence of
[ Hass
Intersections of
curves
Israel
J
.Math
.1985
R
{RI R is
a component of $ ' l N ( P))$ ⇐
S
, EThml
⇒ elk )= ( (D. 4) E CID . SDE
) ( ( D)
= ( ( P ) =m
⇒
IRI
= m -12
OE NE
m -12
( max ( D , n )
: =
max { CCD.SI/lsl=n}
( min ( D , n )
: =
min{ CCD , s)
/ 1st
Thank
you
for your listening !