Spaces of embeddings: new directions
Danica Kosanović Zürich, 10.12.2019
Spaces of embeddings: new directions Danica Kosanovi Zrich, - - PowerPoint PPT Presentation
Spaces of embeddings: new directions Danica Kosanovi Zrich, 10.12.2019 G o a l u n d e r s t a n d s p a c e s o f s m o o t h e m b e d d i n g s ( w i t h W h i t n e y C t o p o l o
Spaces of embeddings: new directions
Danica Kosanović Zürich, 10.12.2019
u n d e r s t a n d s p a c e s
s m
h e m b e d d i n g s
( w i t h W h i t n e y C tG
l
smooth compact manifolds with cou n d e r s t a n d s p a c e s
s m
h e m b e d d i n g s
( w i t h W h i t n e y C tG
l
smooth compact manifolds withFix
Then coflap
= V tapu n d e r s t a n d s p a c e s
s m
h e m b e d d i n g s
( w i t h W h i t n e y C tG
l M
i v a t i
Classical knot theory
smooth compact manifolds withFix
ThenHuh
?!w.fi#=tnotYisotopy
coHap
u n d e r s t a n d s p a c e s
s m
h e m b e d d i n g s
( w i t h W h i t n e y C tG
l M
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Classical knot theory Higher-dimensional knots Knot families
Diffeomorphism groups
smooth compact manifolds withFix
Then45
'Eoubfp
, M)172,2
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V :P ⇐ Mflop
My main project concerns the case and the following problem.
For n>0 the evaluation map gives a universal Vassiliev additive knot invariant of type <n.
P
My main project concerns the case and the following problem.
For n>0 the evaluation map gives a universal Vassiliev additive knot invariant of type <n.
The tower of spaces ... ... and evaluation maps come from the embedding calculus of Goodwillie and Weiss '99. This is a powerful technique for studying any space of embeddings . By Goodwillie and Klein '15 if dim(M) - dim(P) > 2 then becomes increasingly better approximation. They predict that for dim(P)=1, dim(M)=3 is surjective on components.
P
= I ' Wn : Embo (I . I 3) →I →I -I → eunI
My main project concerns the case and the following problem.
For n>0 the evaluation map gives a universal Vassiliev additive knot invariant of type <n.
Theory of finite type invariants by Vassiliev '90. E.g. all quantum invariants are of finite type. Many questions remain open... Geometrically studied by Gusarov '00, Habiro '00, Conant-Teichner '04. The last uses capped grope cobordisms. This gives a filtration on the monoid of knots:
The tower of spaces ... ... and evaluation maps come from the embedding calculus of Goodwillie and Weiss '99. This is a powerful technique for studying any space of embeddings . By Goodwillie and Klein '15 if dim(M) - dim(P) > 2 then becomes increasingly better approximation. They predict that for dim(P)=1, dim(M)=3 is surjective on components.
P
Eoubfp
, M)I
'HI :=to Emboli .IM
em . .For each n>0 the evaluation map gives a universal additive Vassiliev knot invariant of type <n, meaning that the induced map on path components is a monoid homomorphism which factors as and the horizontal map is an isomorphism.
eun : Embo (I . I 3) → I 'ik!
. ' II n Et TOIFor each n>0 the evaluation map gives a universal additive Vassiliev knot invariant of type <n, meaning that the induced map on path components is a monoid homomorphism which factors as and the horizontal map is an isomorphism.
This was proven in BCKS'17. This is the meaning of universality. This is an equivalence relation that uses gropes. eun : Endo , (I . I 3) → I"
¥
.Et TOI
←For each n>0 the evaluation map gives a universal additive Vassiliev knot invariant of type <n, meaning that the induced map on path components is a monoid homomorphism which factors as and the horizontal map is an isomorphism.
Theorem [K.] The horizontal map is surjective.
This was proven in BCKS'17.This is also one case of the Goodwillie-Klein prediction. It will follow from a more general result we state later.
eun : Embo (I . I 3) → I7
"¥t
' II n E- IoT
Two knots are n-equivalent K ~ K' if there is a finite sequence of capped grope cobordisms of degree n from K to K'. Definition.
hTwo knots are n-equivalent K ~ K' if there is a finite sequence of capped grope cobordisms of degree n from K to K'. A capped grope cobordism of degree n is a certain 2-complex built
with n labelled leaves. Definition.
hTwo knots are n-equivalent K ~ K' if there is a finite sequence of capped grope cobordisms of degree n from K to K'. A capped grope cobordism of degree n is a certain 2-complex built
with n labelled leaves. Examples. Definition.
hi
. ⇐ o . K 'v
l K ' ° ⇐ UThe knots are both isotopic to the trefoil T. and Hence: U ~ T and U ~ T. Examples continued.
A 2The knots are both isotopic to the trefoil T. and Hence: U ~ T and U ~ T. But, one can prove that U ~ T. Moreover, T is the generator of . Examples continued. Theorem [Gusarov '00, Habiro '00, Conant-Teichner '04] is a finitely generated abelian group.
Mh
.Whn
The knots are both isotopic to the trefoil T. and Hence: U ~ T and U ~ T. But, one can prove that U ~ T. Moreover, T is the generator of . Examples continued. Theorem [Gusarov '00, Habiro '00, Conant-Teichner '04] is a finitely generated abelian group. However, this group has not been computed for any n > 7.
1 2 13Kh
. I n "'Is: in
#
÷ ÷ ÷
'Theorem [Conant-Teichner '04b] There is a surjective homomorphism of abelian groups .
Here is the abelian group generated by rooted planar binary trees with <n leaves modulo certain relations (related to graph complexes).
Ren
: Atanas I na:
Theorem [Conant-Teichner '04b] There is a surjective homomorphism of abelian groups . Theorem [Kontsevich '93, Bott-Taubes '94, Altschuler-Freidel '97] has a rational inverse (This is a universal additive Vassiliev invariant over Q.)
Here is the abelian group generated by rooted planar binary trees with <n leaves modulo certain relations (related to graph complexes).
Ren
: Atanas I nat
.Ran
Atan ④ Q
IOpen Problems.
Theorem [Conant-Teichner '04b] There is a surjective homomorphism of abelian groups . Theorem [Kontsevich '93, Bott-Taubes '94, Altschuler-Freidel '97] has a rational inverse (This is a universal additive Vassiliev invariant over Q.)
Here is the abelian group generated by rooted planar binary trees with <n leaves modulo certain relations (related to graph complexes).
Ren
: Atanas I na:
Ren
Atan ④ Q
I t na:
Ron
: At Eos I nTheorem [K.] The following diagram commutes:
d
d is given by higher differentials in the Bousfield-Kan spectral sequence.t
Ann
Ray y
B. B. Amikyn
Io T
Theorem [K.] The following diagram commutes:
d
In particular, this proves one half of the Conjecture: is surjective.
d is given by higher differentials in the Bousfield-Kan spectral sequence.t
Ann
Ray \
B.B. A.ikyn
TOI
etn
Theorem [K.] The following diagram commutes:
collapses on the second page along the diagonal), then is a universal additive Vassiliev invariant over A.
d
In particular, this proves one half of the Conjecture: is surjective.
d is given by higher differentials in the Bousfield-Kan spectral sequence.t
Ann
Ray \
b. B. Amikyn
TOI
ein
etnRen
lIo T
A large part of [K] is devoted to developing tools for proving that the two roles of trees
I
Embo(I . M)I
am I . .A large part of [K] is devoted to developing tools for proving that the two roles of trees
Another important ingredient of the proof is the following theorem from our joint work.
For a capped grope cobordism from K to K' there is a path in T from ev (K) to ev (K'). Moreover, this gives a continuous map from the space of gropes on K' to the fibre of
I
Embo(I. M)I
The crucial geometric manoeuvre for [KST]: The symmetric surgery on a capped torus
The crucial geometric manoeuvre for [KST]: The symmetric surgery on a capped torus
References. Current and future projects.