H
IGHERL
ODAY ALGEBRASNorbert Poncin
University of Luxembourg
Geometry of Manifolds and Mathematical Physics Krakow 2011
O
UTLINEHigher (Lie and) Loday (Leibniz) algebras:
1 Coalgebraic approach
2 Category theoretical standpoint
3 Operadic view
4 Supergeometric framework
L
IE ANDL
ODAY INFINITY CATEGORIESC
OALGEBRAIC APPROACHL
∞ ALGEBRAS:
HOMOTOPY INVARIANT EXTENSIONS OFDGLA
S(L,d)
→p
←i (V,d′) pi=idV,ip∼h idL
(L,d) :DGLA⇒(V,d′) :L∞algebra THEOREM
(L,d)and(V,d′)homotopy equivalent ds. AnL∞structure on L induces anL∞structure on V .
⇝Importance ofL∞in BRST, closed string theory
L
∞ ALGEBRAS: DQ
OFP
OISSON MANIFOLDS(V,[−,−]) :GLA,𝜋 ∈V1,[𝜋, 𝜋] =0 𝔤:=𝜈V[[𝜈]],(𝔤,[−,−], ∂𝜋): DGLA
𝜋𝜈 =𝜋+𝜎, s.th. 𝜎∈MC(𝔤) ={s∈𝔤1:∂𝜋s+12[s,s] =0}
Def(𝔤) =MC(𝔤)/G(𝔤) Def:L∞→Set THEOREM
If F :L→L′ is a Qiso, thenDef(F) :Def(L)→Def(L′)is bijective.
L= (Tpoly(M) = Γ(∧TM),[−,−]SN,0): DGLA L′= (Dpoly(M)⊂ ℒ∙(C∞(M)),[−,−]G, ∂𝜇): DGLA
L
∞ ALGEBRAS𝜋p: (sV)∨p→sV, 𝜋:S(sV)→sV
L∞(V)
∥ +
{(𝜋1, 𝜋2, 𝜋3, . . .), multilin., AS,∣𝜋p∣=2−p}
CoDiff1(S(sV))
∥ +
CoDer1(S(sV))
≃
≃
1)𝜋12=0 2)𝜋1der. of𝜋2 3)𝜋2Jacobi id. modulo homotopy Example: (𝜋1, 𝜋2,0, . . .)DGLA
seq. conditions
Q2=0= [Q,Q]
≃
L
∞ ALGEBRAS𝜋p: (sV)∨p→sV, 𝜋:S(sV)→sV
L∞(V)
∥ +
{(𝜋1, 𝜋2, 𝜋3, . . .), multilin., AS,∣𝜋p∣=2−p}
CoDiff1(S(sV))
∥ +
CoDer1(S(sV))
≃
≃
1)𝜋12=0 2)𝜋1der. of𝜋2 3)𝜋2Jacobi id. modulo homotopy Example: (𝜋1, 𝜋2,0, . . .)DGLA
seq. conditions
Q2=0= [Q,Q]
≃
L
∞ ALGEBRAS𝜋p: (sV)∨p→sV, 𝜋:S(sV)→sV
L∞(V)
∥ +
{(𝜋1, 𝜋2, 𝜋3, . . .), multilin., AS,∣𝜋p∣=2−p}
CoDiff1(S(sV))
∥ +
CoDer1(S(sV))
≃
≃
1)𝜋12=0 2)𝜋1der. of𝜋2 3)𝜋2Jacobi id. modulo homotopy Example: (𝜋1, 𝜋2,0, . . .)DGLA
seq. conditions ≃ Q2=0= [Q,Q]
Lod
∞ ALGEBRAS [AMMAR, P, ’08]Lod∞(V)
∥ +
@
@
{(𝜋1, 𝜋2, 𝜋3, . . .), multilin., AS,∣𝜋p∣=2−p}
CoDiff1(T(sV))
∥ +
CoDer1(T(sV))
≃?
≃?
1)𝜋21=0 2)𝜋1der. of𝜋2 3)𝜋2Jacobi id. modulo homotopy Example:(𝜋1, 𝜋2,0, . . .)DGLodA
? seq. conditions ≃? Q2=0= [Q,Q]
T
WISTED COASSOCIATIVE COALGEBRATHEOREM
Δ(v1⊗. . .⊗vp−1⊗vp) =
∑p−2 i=1
∑
𝜎∈sh(i,p−1−i)±v𝜎(1)⊗. . .⊗v𝜎(i)⊗
v𝜎(i+1)⊗. . .⊗ v𝜎(p−1)⊗vp
(T(V),Δ):twistedcoassociative coalgebra, i.e.
(id⊗
Δ)Δ = (Δ⊗
id)Δ +(T⊗
id)(Δ⊗ id)Δ
Lod
∞ CONDITIONSTHEOREM
Cn=
∑
i+j=n+1
∑
k≥j
∑
𝜎∈sh(k−j,j−1)
𝜒(𝜎)(−1)(k+i−j)(j−1)(−1)j(v𝜎(1)+...+v𝜎(k−j)) 𝜋i(v𝜎(1), ...,v𝜎(k−j), 𝜋j(v𝜎(k+1−j), ...,v𝜎(k−1),vk),vk+1, ...,vn) =0,
𝜒(𝜎) :Koszul sign, n≥1.
Lod
∞ COHOMOLOGYLod∞(V)
∥ +
{seq. 𝜋= (𝜋1, 𝜋2, . . .)multilin.,∣𝜋p∣=2−p}
[𝜋, 𝜋]Stem=0?
Cochain space={seq. multilin.}
[−,−]Stem?
⇝Lod∞cohomology ?
Lod
∞ COHOMOLOGYLod∞(V)
∥ +
{seq.𝜋 = (𝜋1, 𝜋2, . . .)multilin.,∣𝜋p∣=2−p}
CoDiff1(T(sV))
∥ +
CoDer1(T(sV))
≃
≃
[𝜋, 𝜋]Stem=0 ≃ Q2=0= [Q,Q]
Cochain space={seq. multilin.} ≃ CoDer(T(sV))
≃ [−,−]
[−,−]Stem
⇝Lod∞cohomology
S
TEM BRACKETTHEOREM
[𝜋, 𝜌]Stem=∑
q≥1
∑
s+t=q+1
(−1)1+(s−1)⟨e1,𝜌⟩[𝜋s, 𝜌t]Stem,
[A,B]Stem=jAB−(−1)⟨(A,a),(B,b)⟩jBA,
jBA= (−1)⟨A,B⟩∑
I∪J∪K=N(a+b+1) I,J<K,∣J∣=b
(−1)⟨B,VI⟩+b∣I∣(−1)(I;J)𝜀V(I;J)
A(VI ⊗B(VJ⊗vk1)⊗VK∖k1)
D
ESCENDANTSTHEOREM
[𝜋,−]Stemencodes
graded Loday (DT), graded Lie (LMS), graded Poisson, graded Jacobi (GM, up to isom) cohomologies
Loday infinity, Lie infinity (FP),2n-ary graded Loday and Lie(MV, VV) cohomologies
C
ATEGORY THEORETICAL APPROACHC
ATEGORIFICATION-
A SHARPER VIEWPOINTSets⇝categories Maps⇝functors
Equations⇝natural isomorphisms + coherence laws
1 vs≃linear set⇝2vs≃linear category
2 LA≃vs + bilinear map + AS, Jacobi
⇝
L2A≃2vsL+ bilinear functor[−,−]+ trilinear natural isomorphismJ : [−,[−,−]]+↻⇒ 0 + coherence laws Semistrict L2A [Baez, Crans, ’04], weak L2A [Roytenberg,
’07]
2
CATEGORIES2 category (rough description):
objectsA,1-morphismsf :A→B,2-morphisms 𝛼:f ⇒f′ (homological algebra, string theory)
vertical composition:f,f′,f′′∈Hom(A,B),𝛼:f ⇒f′, 𝛽 :f′ ⇒f′′,
𝛼∙𝛽 :f ⇒f′′
functorial horizontal composition:
∘:Hom(A,B)×Hom(B,C)→Hom(A,C)is a bifunctor, i.e.
is s.th. if𝛼:f ⇒f′,𝛽 :g⇒g′, then 𝛼∘𝛽 :f ∘g ⇒f′∘g′
H
ORIZONTAL AND VERTICAL COMPOSITIONS
∙ CC∙ CC∙
∙ //EE
∙
~~
∙ // // CC∙
2
CATEGORYLie2Alg
Objects: L2A(L,[−,−],J),(L′,[−,−]′,J′), . . . 1-morphisms:
lin funF :L→L′
bilin natural isoF2: [−,−]′∘(F ⊗F)⇒F ∘[−,−]
respect of Jacobiators 2-morphisms:
lin natural transfo𝜃:F :L→L′⇒G:L→L′ respect ofF2andG2
2vs:s,t :L1→L0 + 1,∘; 2term:𝜋1:V1→V0; 𝜋1=t∣kers Lie2Alg
≃2TermL∞
2
CATEGORYLie2Alg
Objects: L2A(L,[−,−],J),(L′,[−,−]′,J′), . . . 1-morphisms:
lin funF :L→L′
bilin natural isoF2: [−,−]′∘(F ⊗F)⇒F ∘[−,−]
respect of Jacobiators 2-morphisms:
lin natural transfo𝜃:F :L→L′⇒G:L→L′ respect ofF2andG2
2vs:s,t :L1→L0 + 1,∘; 2term:𝜋1:V1→V0; 𝜋1=t∣kers Lie2Alg≃2TermL∞
2
CATEGORYLod2Alg
THEOREM
Lod2Alg≃2TermLod∞ Suppression of AS = destruction of simplifications Conceptual approach to and explicit formulae for 1- and 2-morphisms
C
ATEGORIFICATION VS.
HOMOTOPIFICATION[KHUDAVERDYAN, MANDAL, P, ’10]
Conjecture 1:LnA≃nTermL∞
L2A ∼ catL fun[−,−] transJ coh
L3A :∼ 2-catL 2-fun[−,−] 2-transJ 2-modI ?coh?
↕ ↕ (1) ↕ (2) ↕ (3) ↕ (4) ↕ (5)
3TermL∞ ∼ Vi, 𝜋1,C1 𝜋2,C2 𝜋3,C3 𝜋4,C4 C5 Answer 1a: (5) involves more than 100 terms
Answer 1b: (2) is “[−,−]respects∘ ↔C2” and holds true only under two (acceptable)conditions
C
ATEGORIFICATION VS.
HOMOTOPIFICATIONFact:Vectn-Catis a symmetric monoidal category L×L′ → L′′
⊠ ↓ ↗ L⊠L′
!⊠:L×L′ →L⊠L′ is not ann-functor ! (★)
Conjecture 2: Use
𝒩 :VectCat→s(Vect),N :s(Vect)→C+(Vect), EZ:N(S)⊗N(T)↔N(S⊗T) :AW
Answer 2:Obstruction = defect (★)
O
PERADIC APPROACHD
EFINITION OF AN OPERAD5 definitions:
classical, partial compositions, type of algebras, functorial, combinatorial
algebra→matrices, operad→algebra operad:
vsP(n),n∈ℕ∗, of abstractn-ary operations -Tn
Sn-module structure onP(n) linear composition maps
𝛾i1...ik :P(k)⊗P(i1)⊗. . .⊗P(ik)→P(i1+. . .+ik), which are associative, respect theS-action (and possibly the unit)
D
EFINITION OF AN OPERAD5 definitions:
classical, partial compositions, type of algebras, functorial, combinatorial
algebra→matrices, operad→algebra operad:
vsP(n),n∈ℕ∗, of abstractn-ary operations -Tn Sn-module structure onP(n)
linear composition maps
𝛾i1...ik :P(k)⊗P(i1)⊗. . .⊗P(ik)→P(i1+. . .+ik), which are associative, respect theS-action (and possibly the unit)
O
PERADS ASSOCIATED TO TYPES OF ALGEBRASExample:
AA
P(1) =𝕂T1
P(2) =𝕂T2(12) +𝕂T2(21)(encoding of symmetries) P(3) =𝕂T2(T2,T1) +𝕂T2(T1,T2)(encoding of defining relations)
P(n) =𝕂[Sn] General case:
type of algebras
generating operations with symmetries⇝Sn-moduleM(n) defining relations⇝ideal (R)
operadP=ℱ(M)/(R)
T
WISTING MORPHISMSA: D(GA)A, C: D(GA)C, suspensions + reductions understood Homalg(T(C),A)≃Hom𝕂(C,A)≃Homcoalg(C,Tc(A)) ΩC: DAcobar complex, BA: DC bar complex
d2(a1⊗. . .⊗an) =∑
±a1⊗. . .⊗𝜇(ai,ai+1)⊗. . .⊗an
HomDA(ΩC,A)≃TW(C,A)≃HomDC(C,BA) Qiso(ΩC,A)≃Kos(C,A)≃Qiso(C,BA)
d𝛼 :C⊗AΔ⊗id→ C⊗C⊗Aid⊗𝛼⊗id→ C⊗A⊗Aid→⊗𝜇C⊗A
ΩBA→∼ A: bar-cobar resolution of A
K
OSZUL DUALITY FOR ALGEBRAS AND OPERADS Quadratic data:V,R⊂V⊗2(e.g. R=⟨v ⊗v′−v′⊗v⟩) Quadratic algebra:A(V,R) =T(V)/(R)⊃𝕂⊕V (e.g. S(V)) Quadratic coalgebra:C(V,R) =𝕂⊕V ⊕⊕
k≥2
∩
i+j+2=k
V⊗i⊗R⊗V⊗j ⊂Tc(V) Koszul dual coalgebra ofA(V,R):
A¡ =C(sV,s2R)⊃𝕂⊕sV TW(A¡,A)∋𝛼:A¡ ↠sV →V ↣A
If𝛼∈Kos(A¡,A), then
ΩA¡ →∼ A
Extension of this minimal model ofKoszul algebras[Priddy, ’70]
toKoszul operads[Ginzburg, Kapranov, ’94]
I
NFINITY ALGEBRAS VIA OPERADSEnd(V): endomorphism operad on a vsV
P→End(V): operadic morphism,typeP algebra structure onV
IfP is aKoszul operad,
P∞:=
ΩP¡ →∼ P
↘ ↓
End(V)
FromΩℒie¡andΩℒod¡we recoverL∞andLod∞structures onV
I
NFINITY ALGEBRAS VIA OPERADSEnd(V): endomorphism operad on a vsV
P→End(V): operadic morphism,typeP algebra structure onV
IfP is aKoszul operad,
P∞:=ΩP¡ →∼ P
↘ ↓
End(V)
FromΩℒie¡andΩℒod¡we recoverL∞andLod∞structures onV
O
CCURRENCES OFL
ODAY ANDLod
∞ ALGEBRASLeibniz (Loday) algebras
★Origin: periodicity phenomena inK-theory
★Examples:
1 Courant-Dorfman bracket, Courant algebroid bracket
2 Loday bracket associated with a Nambu-Poisson structure
3 Derived brackets Loday infinity algebras
★Origin: universal GLA and cohomologies
★Examples:
1 Fulton-MacPherson type compactification [Kontsevich, ’03]
[Merkulov, ’09]
2 Formal deformation of a DGLodA and derived brackets [Uchino, ’09]
S
UPERGEOMETRIC APPROACHK
OSZUL DUALITY FOR OPERADS REVISITEDGinzburg-Kapranov, ’94:
P∞-algebra onV ⇌Q∈Der1(ℱPgr!(sV∗)),Q2=0 Example:
L∞-algebra⇌homological vf on apointed formal smfd Geometric ‘example’:
L∞-algebroid⇌homological vf on asplitℕ-mfd Particular case:
LAD⇌homological vf on asplit smfd
R
EQUIREMENTSFind a concept ofLoday algebroidthat is close to the notion of Lie algebroid
contains Courant algebroids as special case reduces to a Loday algebra over a point
includes a differentiability condition on both arguments, and interpret it ashomological vf on a supercommutative mfd
L
ODAY ALGEBROIDS:
FIRST ATTEMPT‘Definition’: ALoday algebroidis a Loday bracket[−,−]on sections of a vbE together with aleft and right anchor J. Grabowski, G. Marmo:
Ifrk(E) =1,[−,−]is AS and 1st order Ifrk(E)>1,[−,−]is ‘locally’ aLAD bracket
‘No’ new examples⇝modify ‘definition’
L
ODAY ALGEBROIDS:
SECOND ATTEMPT𝜌: Γ(E)→DerC∞(M),C∞(M)-linear
∂x(fY) =∂xf Y +f ∂xY,∂x2(fY) =∂2xf Y +2∂xf∂xY +f ∂x2Y [X,fY] =f[X,Y] +𝜌(X)f Y
[Xiei,fYjej] =
XiakijfYj ek+Xi𝜌ai∂af Yjej+Xi𝜌ai f ∂aYj ej−Yi𝜌ai∂aXj ej 𝜌(X)(df⊗Y) =Xi𝜌akij ∂af Yjek
𝜌: Γ(E)C
∞(M)−lin
−→ Γ(TM)⊗C∞(M)EndC∞(M)Γ(E) 𝜌:E →TM⊗EndE
Cohomology theory⇝representation,traditional left anchor
D
EFINITION [GRABOWSKI, KHUDAVERDYAN, P, ’11]DEFINITION
ALoday algebroid(LodAD) is a Loday bracket on sections of a vb E→M together with two bundle maps𝜌:E→TMand
𝛼:E→TM⊗EndE such that
[X,fY] =f[X,Y] +𝜌(X)f Y and
[fX,Y] =f[X,Y]−𝜌(Y)f X+𝛼(Y)(df ⊗X).
C
OURANT ALGEBROID ET ALEXAMPLES
Loday algebra
(twisted) Courant-Dorfman (TM⊕T∗M)
Grassmann-Dorfman (TM⊕ ∧T∗M orE⊕ ∧E∗)
Leibniz algebroid associated to a Nambu-Poisson structure Courant algebroid
...
E
XTENSION TOL
ODAY ALGEBROIDS(I)
(E,[−,−], 𝜌)⇌Q∈Der1(Γ(∧E∗),∧),Q2=0 (E,[−,−], 𝜌)→LAD cohomology operator∂𝜌
∂𝜌is the C-E operator restricted to
∧C∞(M)(Γ(E),C∞(M)) = Γ(∧E∗)
∂𝜌is the Loday operator restricted to LinC∞(M)
D
(Γ(E),C∞(M)) = Γ(⊗E∗)
=:D(E)
(D⋔Δ)(X1, . . . ,Xp+q)
= ∑
𝜎∈sh(p,q)
sign(𝜎)D(X𝜎1, . . . ,X𝜎p) Δ(X𝜎p+1, . . . ,X𝜎p+q)
E
XTENSION TOL
ODAY ALGEBROIDS(I)
(E,[−,−], 𝜌)⇌Q∈Der1(Γ(∧E∗),∧),Q2=0 (E,[−,−], 𝜌)→LAD cohomology operator∂𝜌
∂𝜌is the C-E operator restricted to
∧C∞(M)(Γ(E),C∞(M)) = Γ(∧E∗)
∂𝜌is the Loday operator restricted to
LinC∞(M)
D(Γ(E),C∞(M))
= Γ(⊗E∗)
=:D(E)
(D⋔Δ)(X1, . . . ,Xp+q)
= ∑
𝜎∈sh(p,q)
sign(𝜎)D(X𝜎1, . . . ,X𝜎p) Δ(X𝜎p+1, . . . ,X𝜎p+q)
E
XTENSION TOL
ODAY ALGEBROIDS(I)
(E,[−,−], 𝜌)⇌Q∈Der1(Γ(∧E∗),∧),Q2=0 (E,[−,−], 𝜌)→LAD cohomology operator∂𝜌
∂𝜌is the C-E operator restricted to
∧C∞(M)(Γ(E),C∞(M)) = Γ(∧E∗)
∂𝜌is the Loday operator restricted to
LinC∞(M)
D(Γ(E),C∞(M))
= Γ(⊗E∗)
=:D(E)
(D⋔Δ)(X1, . . . ,Xp+q)
= ∑
𝜎∈sh(p,q)
sign(𝜎)D(X𝜎1, . . . ,X𝜎p) Δ(X𝜎p+1, . . . ,X𝜎p+q)
E
XTENSION TOL
ODAY ALGEBROIDS(II)
(E,[−,−], 𝜌, 𝛼)⇌Q∈Der1(D(E),⋔),Q2=0
𝒟k(E)⊂Dk(E):k-DO of deg 0 in last section and tot degk −1 𝒟k(E)⋔𝒟ℓ(E)⊂ 𝒟k+ℓ(E): reduced shuffle algebra
∂𝜌𝒟k(E)⊂ 𝒟k+1(E): LodAD subcomplex
E
XTENSION TOL
ODAY ALGEBROIDS(III)
(E,[−,−], 𝜌, 𝛼)⇌Q∈Der1(𝒟(E),⋔),Q2=0
𝜌(X)f :=⟨Qf,X⟩
⟨ℓ,[X,Y]⟩=⟨X,Q⟨ℓ,Y⟩⟩ − ⟨Y,Q⟨ℓ,X⟩⟩ −(Qℓ)(X,Y)
Q(𝒟2(E))↮Q(𝒟0(E)⊕ 𝒟1(E))
𝒟er1(𝒟(E),⋔)⊂Der1(𝒟(E),⋔): deg 1 der + appropriate rel (E,[−,−], 𝜌, 𝛼)⇌Q∈ 𝒟er1(𝒟(E),⋔),Q2=0
(E,[−,−], 𝜌, 𝛼)⇌[Q]∈ 𝒟er1(𝒟(E),⋔),Q2=0
L
ODAD
AS HOMOLOGICAL VFTHEOREM
There is a 1-to-1 correspondence between LodAD structures on a vb E andequivalence classes of homological vfs
Q∈ 𝒟er1(𝒟(E),⋔),Q2=0 of the supercommutative mfd(𝒟(E),⋔).
Remarks: Homological vfQ⇝ Cartan calculusfor(D(E),⋔)
LodAD bracket isderived bracketgiven by gLa (Der(D(E),⋔),[−,−]c)and its interior der[Q,−]c
R
EFERENCES1 M. Ammar, P,Coalgebraic Approach to the Loday Infinity Category, Stem Differential for 2n-ary Graded and Homotopy Algebras, Ann. Inst. Fourier, 60(1), 2010, pp 321-353
2 D. Khudaverdyan, A. Mandal, P,Equivalence of the 2-categories of categorified Loday algebras and 2-term Loday infinity algebras, draft
3 D. Khudaverdyan, A. Mandal, P,Higher categorified algebras versus bounded homotopy algebras, Theo. Appl.
Cat., Vol. 25, No. 10, 2011, pp 251-275
4 P. Hilger, A. Mandal, P,Lectures on Operad Theory, preprint
5 J. Grabowski, D. Khudaverdyan, P,Loday algebroids and their supergeometric interpretation, preprint arXiv:
1103.5852