Higher order Dirac structure and Nambu-Poisson geometry

Yanhui BI , Jia LI

Front. Math. China ›› 2024, Vol. 19 ›› Issue (1) : 37 -56.

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Front. Math. China ›› 2024, Vol. 19 ›› Issue (1) : 37 -56. DOI: 10.3868/s140-DDD-024-0004-x
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Higher order Dirac structure and Nambu-Poisson geometry

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Abstract

This paper studies the properties of Nambu-Poisson geometry from the (n−1, k)-Dirac structure on a smooth manifold M. Firstly, we examine the automorphism group and infinitesimal on higher order Courant algebroid, to prove the integrability of infinitesimal Courant automorphism. Under the transversal smooth morphism ϕ:NM and anchor mapping of M on (n−1, k)-Dirac structure, it’s holds that the pullback (n−1, k)-Dirac structure on M turns out an (n−1, k)-Dirac structure on N. Then, given that the graph of Nambu-Poisson structure takes the form of (n−1, n−2)-Dirac structure, it follows that the single parameter variety of Nambu-Poisson structure is related to one variety closed n-symplectic form under gauge transformation. When ϕ:NMis taken as the immersion mapping of (n−1)-cosymplectic submanifold, the pullback Nambu-Poisson structure on M turns out the Nambu-Poisson structure on N. Finally, we discuss the (n−1, 0)-Dirac structure on M can be integrated into a problem of (n−1)-presymplectic groupoid. Under the mapping Π: MM/H, the corresponding (n−1, 0)-Dirac structure is F and E respectively. If E can be integrated into (n−1)-presymplectic groupoid (g,Ω), then there exists the only ω¯, such that the corresponding integral of F is (n−1)-presymplectic groupoid (g,¯ω¯).

Keywords

Nambu-Poisson structure / n-symplectic structure / (n−1, k)-Dirac structure / integrability

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Yanhui BI, Jia LI. Higher order Dirac structure and Nambu-Poisson geometry. Front. Math. China, 2024, 19(1): 37-56 DOI:10.3868/s140-DDD-024-0004-x

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1 Introduction

Dirac structure is a geometric structure introduced by Courant and Weinstein [10, 11] on differential manifold M, namely the maximally isotropic subbundle of the direct sum bundle TMTM, covering Poisson structure, presymplectic structure, complex structures, and foliation structure. The research on Dirac structure contributed to rapid development of Courant algebroid, higher order structure and generalized complex geometry [12, 13]. The Courant algebroid introduced by Liu et al. [17] comprised of a non-degenerate symmetric pairing, a bracket operation and an anchor mapping, to study the double of Lie bialgebroid (see [17]), with its equivalent definition presented by Roytenberg [21]. One important property of Courant algebroid lies in that its sectional space is a Lie 2-algebra, which establishes relevance between Poisson geometry and higher order structure, so as to study higher order Lie theory. Especially in the recent decade, there has been research on mathematical physics and Poisson geometry from the two directions of Dirac geometry and higher order structure. For example, reference [7] proved that the Poisson homogeneous space of any Poisson Lie group could be integrated with Dirac geometry; reference [2] studied the integrability of Poisson structure and Dirac geometry on quotient manifold; references [3, 25] presented the concept of higher order Courant algebroid on TMn1TM; reference [5] introduced the concept of n-omni Lie algebroid; reference [16] led in the concept of omnin-Lie algebroid; references [4, 8] primarily studied higher order Dirac structure, covering Nambu-Poisson structure (see [14]) and multisymplectic geometry structure [6]; reference [22] presented the relationship between Dirac structure of higher order Courant algebroid and Lie n-algebra.

Yoichiro [20] first proposed the Nambu-Poisson bracket on a smooth manifold M. Nambu-Poisson structure, given by Takhtajan [24], was used to study the problem of Nambu-Hamilton system. Reference [3] obtained that the n-vector field π is a Nambu-Poisson structure, and its graph would be closed if and only if under the higher order Courant bracket, establishing a one-to-one correspondence between the higher order Dirac structure and Nambu-Poisson structure. References [3, 6] introduced the n-presymplectic structure, and pointed out that if the graph of the n-presymplectic structure turns out a Dirac structure, then the graph of n-symplectic form ω would be closed under higher order Courant bracket. Reference [4] introduced the concept of (p, k)-Dirac structure on higher order Courant algebroid. Reference [7] demonstrated that on the principal bundle MM/H, if the Dirac structure on M/H contained H-compatible presymplectic groupoid, the presymplectic groupoid could be obtained after pulling back the Dirac structure to M. Through the correspondence between the Nambu-Poisson structure, n-symplectic structure and (n−1, k)-Dirac structure, this paper further investigates the relationship between the (n−1, k)-Dirac structure and the Nambu-Poisson geometry

Section 2 gives an overview of the basic knowledge and related concepts. Section 3 presents the automorphism group (ωt,Φt)AutCA(Tn1M) and automorphism Lie algebra (γt,Xt)AutCA(Tn1M)(γt,Xt)AutCA(Tn1M) form of Courant algebroid on (n−1, k)-Dirac structure, hence proving the integrability of infinitesimal Courant automorphism. Then (n−1, k)-Dirac morphism is introduced to study the (n−1, k)-Dirac structure which can be pulled back under diffeomorphism. Section 4 demonstrates the graph of Nambu-Poisson structure is in an (n−1, n−2)-Dirac structure, and the single parameter variety gauge transformation of Nambu-Poisson structure is related to one variety closed n-symplectic structure ωt=0t((Φs)γs)ds. Section 5 studies the integrability of pullback (n−1, 0)-Dirac structure based on the correspondence between (n−1, 0)-Dirac structure and Lie algebroid. Section 5 is the summary.

2 Prerequisites

In this Section, we first of all review some basic knowledge and relevant concepts mentioned in this paper.

Definition 2.1 [15] The Nambu-Poisson structure on manifold M is an n-linear mapping

{,,}:C(M)××C(M)C(M),

which satisfies the following properties.

(1) Antisymmetry. For any fiC(M)(1in), σSn(Sn is an n-order symmetric group),

{f1,,fn}=(1)ε(σ){fσ(1),,fσ(n)}.

(2) Leibniz property. For any fi,gC(M)(1in),

{f1g,f2,,fn}=f1{g,f2,,fn}+g{f1,f2,,fn}.

(3) Fundamental identity. For any fi,gjC(M)(1in1,1jn),

{f1,,fn1,{g1,,gn}}=j=1n{g1,,{f1,,fn1,gj},,gn}.

If one Nambu-Poisson bracket meets one of the above properties, there exists a multivariate vector field πΓ(nTM) satisfying the equation

π(df1dfn)={f1,,fn}.

If n1TM is the (n−1)-order differential form bundle, then π induces a vector bundle homomorphism

π:n1TMTM.

If the multivariate vector field satisfies Lπ(df1dfn)π=0, then it is called a Nambu-Poisson vector field on manifold M. (M, π) refers to n-order Nambu-Poisson manifold.

Definition 2.2 [8] The higher order Poisson structure on manifold M contains a subbundle SkTM and bundle mapping Λ:STM, such that

(a) S={0};

(b) iΛ(α)β=iΛ(β)α,α,βS;

(c) [α,β]:=LΛ(α)βiΛ(β)dα=LΛ(α)βLΛ(β)αd(iΛ(α)β), and Γ(S) is closed to the bracket, where Λ:Γ(S)Γ(TM) maintains bracket operation. Then (M, S, A) is called k-order Poisson manifold.

Definition 2.3 [9] The multisymplectic structure on manifold M is a closed and non-degenerate differential form ωΩn(M), namely iXω=0 if and only if X=0, equivalently,

ωb:TMn1TM,XiXω

is injective, and we call (M, ω) a multisymplectic manifold.

As is widely known, multisymplectic manifold is a special type of Nambu-Poisson manifold. Given a multisymplectic manifold (M, ω), define

iXf1,,fn1ω=df1dfn1,

the corresponding Nambu-Poisson bracket is

{f1,,fn1,g}=Xf1,,fn1,dg.

Definition 2.4 [26] The n-Lie algebra is the bracket operation [,,]g:ngg of a vector space g and an n-antisymmetry, such that any

[x1,x2,,xn1,[y1,y2,,yn]]g=i=1n[y1,y2,,[x1,x2,,xn1,yi],,yn].

Definition 2.5 [26] Assume M is a manifold, f:EM is a vector bundle, one n-Lie algebroid on manifold M is a quadruple (E,ρ,[,,],M), where section Γ(E) goes with n-bracket [,,] satisfying generalized Jacobi identity, ρ:n1ETM is bundle mapping, which induces Li algebra homomorphism between Γ(n1E) and X(M), namely for any fC(M),X1,,Xn1,YΓ(E), there is

[ρ(X1Xn1),ρ(Y1Yn1)]=i=1n1ρ(Y1[X1,,Xn1,Yi]Yn1),

[X1,,Xn1,fY]=f[X1,,Xn1,Y]+ρ(X1Xn1)(f)Y,

where ρ is anchor mapping.

If π is a Nambu-Poisson structure, then [π,π]=0, the coordinates of Nambu-Possion vector field can be shown as π=1n!πi1in(x)xi1xin, where πi1in is a smooth function.

Definition 2.6 [24] The Nambu-Poissono tensor becomes linear point by point in coordinate representation, specifically as πi1in(x)=πi1iinjxj, which is called linear Nambu-Poisson tensor. Meanwhile, define a linear Nambu-Poisson structure:

{xi1,,xin}(x)=j=1nπi1iinjxj.

The following is to prove the one-to-one correspondence between n-Lie algebroid and linear Nambu-Poisson structure vector bundle. For section XΓ(E), let ϕXC(E) be the corresponding smooth function on dual bundle E.

Theorem 2.1  For any n-Lie algebroid E endowed with n-bracket [,,], where EM is the vector bundle with n as the rank, and on the space of dual bundle, there exists the only Nambu-Poisson bracket {,,} such that for any section X1,,Xn1,YΓ(E), there is

{ϕX1,,ϕXn1,ϕY}=ϕ[X1,,Xn1,Y].

The anchor mapping under the Nambu-Poisson bracket is

p(ρ(X1Xn1)f)={ϕX1,,ϕXn1,pf},

for any fC(M), {ρf1,,ρfn}=0, then the linear Nambu-Poisson structure on E is defined.

Conversely, the fiber linear Nambu-Poisson structure on the vector bundle obtains the n-Lie algebroid structure on the dual bundle.

Proof Assume EM is n-Lie algebroid, select locally trivial bundle E|U=U×Rn on the open set UM, and assume the basis on section is ε1,,εn. Assume x1,,xn are local coordinates on U. Then the differential of the smooth function on dual bundle yi=ϕεi, where function xjyi=ϕxjεi spans T(E), the differential of linear function ϕX spans a dual space, so there exists vector field πXn(E), such that

π(dϕX1,,dϕXn1,dϕY)=ϕ[X1,,Xn1,Y].

To prove the existence of π, we use the definition of n-Lie algebroid structure constant [εi1,,εin]g=k=1nπi1inkεk, and assume ρ(εi1εij1εij^εij+1εin)X(U). yi is the corresponding coordinates on (Rn), then the coordinates of the vector field can be represented as:

π=i1<<in,kπi1inkykyi1yin+i1<<in(1)njyi1^yijyinρij,

which is the only vector field on E|U=U×(Rn).

Conversely, assume p:VM is a vector bundle, π is the corresponding linear Nambu-Poisson structure, and assume E=V is a dual bundle, define n-Lie bracket (2.1) and anchor mapping (2.2) on the sectional space. We can obtain that ρ(X1Xn1) is a vector field directly from the definition of n-Lie algebroid, and the mapping (X1Xn1)ρ(X1Xn1) is a smooth linear mapping. The Jacobi identity of n-bracket can be given by the Nambu-Poisson bracket, and the derivation property of Nambu-Poisson bracket can be inferred from the Leibnitz’s rule of anchor mapping:

ϕ[X1,,Xn1,fY]={ϕX1,,ϕXn1,ϕfY}={ϕX1,,ϕXn1,(pf)ϕY}=(pf){ϕX1,,ϕXn1,ϕY}+p(ρ(X1Xn1)f)ϕY.

Definition 2.7 Let’s call the linear mapping variety ϕE:(E2)ϕM(m)(E1)m dependent on point of m satisfying the commuting graph

E1ϕEE2M1ϕMM2,

the comorphism on the vector bundle, where ϕM:M1M2 is the basis mapping.

Next research is conducted on the direct sum bundle Tn1M=TMn1TM, and we define the value pairing (·,·) of non-degenerate n2TM on the section Γ(Tn1M) as follows:

(X+α,Y+β)+=12(iXβ+iYα),X,YX(M),α,βΩn1(M).

Define bracket , on Γ(Tn1M) as below:

X+α,Y+β=[X,Y]+LXβiYdα,

where anchor mapping ρ is the projection of TMn1TM to TM, we call (TMn1TM,(,)+,·,·,ρ) a higher order Courant algebroid.

Definition 2.8 [4] Let E be the subspace of Vn1, W be the projection of E on a vector space. If 0kn2,e1,e2E,u1,,ukW, there is

iukiu1(e1,e2)+=0,

we call E the (n−1, k)-isotropic subspace. If E=Ek:={vVn1iukiu1(v,E)+=0,u1,,ukW}, and E is (n−1, k)-maximally isotropic, we call E the linear (n−1, k)-Dirac structure.

Reference [3] proved that for any Nambu-Poisson structure πXn(M) on the Nambu-Poisson manifold, the graph of mapping π:n1TMTM is an (n−1)-order Nambu-Poisson structure.

Proposition 2.1 [3, 18]  For any σ1,σ2,σ3Γ(Tn1M),fC(M), there is

(1) σ1,fσ2=fσ1,σ2+ρ(σ1)(f)σ2;

(2) Lρ(σ1)(σ2,σ3)=(σ1,σ2,σ3)+(σ2,σ1,σ3);

(3) [[σ1,σ2,σ3]]=[[σ1,σ2,σ3]]+[[σ2,σ1,σ3]];

(4) fσ1,σ2=fσ1,σ2ρ(σ2)(f)σ1+2(σ1,σ2)df.

3 Morphism of 2(n1, k)-Dirac structure

Similar to the description of Poisson mapping in Dirac geometry, this section presents the morphism of (n−1, k)-Dirac structure, which can be induced to pull back through transversal conditions.

Natural induction of a generalized differential mapping by diffeomorphic mapping is defined by as follows:

Txn1Φ:=dxΦ+n1((dxΦ)1):Txn1MTΦ(x)n1M.

Induce a pullback mapping (Tn1Φ):Γ(Tn1M)Γ(Tn1M) on Tn1Φ, then it follows

(Tn1Φ)(X+α)=Φ(X)+Φ(α),XX(M),αΩn1(M).

Here, the pullback of vector field and differential form is defined as below:

Φ(X)=(dΦ)1XΦ,Φ(α)=(dΦ)αΦ.

Since Tn1Φ maintains bracket operation (·,·) and ·,·, Tn1Φ can induce (n1,k)-Dirac structure (Tn1Φ)(E) out of (n1,k)-Dirac structure on ETn1M, hence the diffeomorphic Dirac structure.

Define AutCA(Tn1M) as an automorphism group of higher order Courant algebroid on Tn1M, AAutCA(Tn1M) maintains bracket operation and anchor mapping. Assume Φ:MM is a basis mapping, and induce Φ:n1TMn2TM, then

(Aσ,Aτ)=Φ(σ,τ),[Aσ,Aτ]=A[σ,τ],ρA=dΦρ.

Any diffeomorphism ΦDiff(M) on M defines standard higher order Courant algebroid automorphism Tn1ΦAutCA(Tn1M), so group homomorphism AutCA(Tn1M)Diff(M) is surjective, and the standard Courant algebroid automorphism Tn1Φ induces a short exact sequence

1Ωcln(M)AutCA(Tn1M)Diff(M)1,

where Ωcln(M) is a set comprised of all closed n-forms on M.

For any closed form, induce a normal transition transformation as the vector bundle isomorphism

Rω:Tn1MTn1M,X+αX+α+iXω.

Lemma 3.1 [4]  The automorphic mapping Rω:Tn1MTn1M maintains the inner product bracket (·,·) of higher order Courant algebroid, anchor mapping ρ and higher order Dorfman bracket ·,· if and only if dω=0.

Theorem 3.1  The automorphism group of Courant algebroid on Tn1M is a semidirect product AutCA(Tn1M)=Ωcln(M)Diff(M).

Proof Assume AAutCA(Tn1M), ΦDiff(M) is a basis mapping, then A=ATn1Φ1 has an identity mapping as the basis mapping. In particular, ρA=ρ, and for any viTMTn1M, Avivin1TM, ω(v1,,vn)=A(v1),(v2,,vn), because A maintains the bracket, hence

0=(A(v1)v1,A(v2)v2)=(A(v1),A(v2))A(v1),v2v1,A(v2)+v1,v2,ω(v1,v2)+ω(v2,v1)=0.

Therefore, ω is antisymmetric, which proves that A=Rω, but Rω maintains the Courant bracket property if and only if ω is closed. It can be seen from the Courant bracket nature that

A(fσ1,σ2)=fAσ1,σ2ρ(σ2)(f)A(σ1)+2(σ1,σ2)A(df),A(fσ1),A(σ2)=fA(σ1),A(σ2)ρ(A(σ2))(f)A(σ1)+2(A(σ1),A(σ2))df.

Since mapping A maintains the bracket, it holds from comparison with the above formula

ρ(σ2)(f)A(σ1)+2(σ1,σ2)A(df)=ρ(A(σ2))(f)A(σ1)+2(A(σ1),A(σ2))df.

Assign σ1=X,σ2=Y, then (σ1,σ2)=0,ρ(σ2)(f)A(σ1)=ρ(A(σ2))(f)A(σ1)Y=ρ(A(Y)). If σ1=α,σ2=Y, then A(df)=df. Based on the above, A(X+α)=X+α+N(X), where N(X) is an (n1)-form. Assume N=ω,A(X+α)=Rω(X+α)=X+α+iXω, with maintained bracket if and only if ω is a closed form.□

Standard ·,· bracket can be deformed by a closed 3-form [12, 23], and we assign an (n+1)-form θ for higher order ·,· bracket, which can be deformed into

X+α,Y+βθ=[X,Y]+LXβiYdα+iXiYθ.

For arbitrarily smooth function Φ, there is Tn1Φ.(X+α),Tn1Φ. (Y+β)θ=Tn1Φ.(X+α,Y+βΦθ). Given a closed n-form ω from Lemma 3.2, Rω(X+α),Rω(Y+β)θ+dω=RωX+α,Y+βθ.

So we can obtain that AutCA(Tn1M)=Ωcln(M)Diff(M).

In the similar way, we approach the the discussion of Lie algebra AutCA(Tn1M) of infinitesimal Courant algebroid automorphism. It can be regarded as an operator on the section, that is in the linear mapping D:Γ(Tn1M)Γ(Tn1M), there exists a vector field X satisfying the following properties:

D(fσ)=fD(σ)+X(f)σ,(Dσ,τ)+(σ,Dτ)=X(σ,τ),Dσ,τ+σ,Dτ=Dσ,τ,ρ(Dτ)=[X,ρ(τ)].

Theorem 3.2 (a) The Lie algebra of infinitesimal Courant automorphism is a semidirect product

AutCA(Tn1M)=Ωcln(M)X(M),

where (γ, X) functions on the section τ=Y+βΓ(TnM) as follows:

(γ,X).τ=[X,Y]+LXβiYγ.

(b) For any section σ=X+αΓ(Tn1M), the role of , bracket is equivalent to infinitesimal automorphism (dα,X).

Proof Assign an injection Ωcln(M)X(M)AutCA(Tn1M) for (a). We prove that it is also surjective. Assume the corresponding basic vector field of DAutCA(Tn1M) is X,LXAutCA(Tn1M), then the corresponding basic vector field of D=DLX is 0. Hence D(fσ)=fD(σ). Furthermore, ρD=0, so the value of automorphism is within n1TM. At the same time, D(ρ(n1TM))=0, so bundle mapping TMn1TM can be obtained. Since D maintains bracket operation,

(DX,Y)+(X,DY)=0.

Therefore, there exists n-form γ, and we obtain D(X+α)=iXγ. Finally, D maintains bracket if and only if γ is closed. The demonstration of (b) can be readily obtained from (a). □

The following studies the relationship between Courant automorphism group and automorphism Lie algebra.

Theorem 3.3  Let (ωt,Φt)AutCA(Tn1M) be a time-dependent automorphism variety, corresponding to infinitesimal automorphism (γt,Xt)AutCA(Tn1M), then

ωt=0t((dtΦ)γs)ds,

where Φt is the flow of Xt.

Proof The flow of the time-dependent vector field works on the function as ddt(dtΦ)=(dtΦ)LXt, and we assume τ=Y+βΓ(Tn1M),(γt,Xt)τ=LXtτiPr1(τ)γt, where the differential of single parameter variety (ωt,Φt) of Pr1(τ)=Y,Tn1M automorphism is (γt,Xt), then (ωt,Φt)τ=(dtΦ)τi((dtΦ)Y)ωt, and we take the derivative of single parameter t at both sides as follows:

ddt((ωt,Φt).τ)=(ωt,Φt).(γt,Xt).τ.

We obtain from left side of the equation

ddt((ωt,Φt),τ)=ddt((dtΦ)τi((dtΦ)Y)ωt)=(dtΦ)LXtτi((dtΦ)LXtY)ωti((dtΦ)Y)dωtdt.

We obtain from right side of the equation

(ωt,Φt).(γt,Xt).τ=(ωt,Φt)(LXtτi(Y)γt)=(dtΦ)(LXtτi(Y)γt)i(dtΦ(Pr1[(LXtτi(Y)γt)]))ωt=(dtΦ)LXtτi((dtΦ)Y)(dtΦ)γti((dtΦ)LXtY)ωt.

We get (dtΦ)γt=dωtdt by comparing the two. □

Definition 3.1 [1] Assume ϕ:NM is a smooth mapping, vector bundle morphism is dϕ:TNTM, comorphism is n1Tϕ:n1TNn1TM,FTn1N,ETn1M are (n−1, k)-Dirac structure on N and M, respectively, and define the pullback morphism of (n−1, k)-Dirac structure as follows:

F:={(X+n1Tϕ(α))Tn1N:dϕX+αTn1M}.

Define the push-forward morphism of (n−1, k)-Dirac structure as follows:

E:={dϕX+αTn1M:X+n1Tϕ(α)Tn1N}.

Its graph is the sum of tangent bundle and higher order cotangent bundle mapping, with the correlation defined as below.

(1) For x=v+μTϕ(p)n1M,y=w+νTpn1N, if v=(dpϕ)w,ν=(n1Tpϕ)μ. We call y and x ϕ relevant, written as yϕx(x,y)Gr(Tn1ϕ).

(2) For σ=X+αΓ(Tn1M),τ=Y+βΓ(Tn1N), if YϕX,β=ϕα, then there is τϕσ on Γ(Gr(Tn1ϕ)).

Tn1ϕ maintains ·,· bracket, and there is the following equivalence in deduction:

τ1ϕσ1,τ2ϕσ2(τ1,τ2)=ϕ(σ1,σ2),τ1ϕσ1,τ2ϕσ2τ1,τ2]ϕ[σ1,σ2],τϕσρ(τ)ϕρ(σ).

Definition 3.2 LetFTn1N, ETn1M be the (n−1, k)-Dirac structure on N and M, ϕ:NM be smooth mapping. If for any pN,xEϕ(p), there exists the only yFp, such that yϕx, then define an (n−1, k)-Dirac comorphism Tn1ϕ:(Tn1N,F)(Tn1M,E).

Definition 3.3 Let (F,ρ1) and (E,ρ2) be the n-Lie algebroid on manifold. If the pullback mapping of Γ(E)Γ(F) maintains bracket and anchor mapping, then n-Lie algebroid comorphism FE is defined.

Assume Tn1ϕ:(Tn1N,F)(Tn1M,E) is an (n−1, k)-Dirac comorphism. From the uniqueness of the definition, we can see that in the linear mappingEϕ(p)Fp, the only yFp is obtained for xEϕ(p), then yϕx. Meanwhile, it is smooth at point p, whereby the comorphism of higher order vector bundle can be defined.

Lemma 3.2  Any (n1,n2)-Dirac morphism Tn1ϕ:(Tn1N,F)(Tn1M,E) defines an n-Lie Algebroid comorphism FE.

Proof We need to prove that the pullback mapping ϕ:Γ(E)Γ(F) maintains the bracket, and the anchor mapping satisfies dϕ(ρ(y))=ρ(x) under the condition of yϕx, which can be proved from the maintained bracket of ϕ:Γ(E)Γ(F).

Theorem 3.4  Let ETn1M be an (n−1, k)-Dirac structure, ϕ:NM transverses across the anchor mapping of E, namely

dxϕ(TxN)+ρ(Eϕ(x))=Tϕ(x)M,xM.

Then ϕ!E={yTn1N|xE:yϕx} is an (n−1,k)-Dirac structure.

Proof We first consider ϕ as an embedded submanifold ϕ:NM. The transversal conditions guarantee that ϕ!E is a subbundle of Tn1N. For any yϕ!E, there exists the only xE:yϕx; we define the corresponding graph of mapping ϕ!EE|N as ρ1(TN)E. Any given section τΓ(ϕ!E) can be prolonged into section σΓ(E) in E, such that τϕσ. Conversely, for any given section σΓ(E), there exists the only τϕσ, such that the anchor mapping is tangent to N.

Under normal circumstances, we consider the embedded mapping of N as the graph of mapping ϕ:

j:NM×N,n(ϕ(n),n),

we get ϕ!E=j!(E×TN)Tn1N.

4 Nambu-Poisson (n1, n2)-Gauge transformation

For any n-vector field π, its graph Gr(π) is an (n−1, n−2)-Dirac structure if and only if π is a Nambu-Poisson structure.

Definition 4.1 [14] A Nambu-Poisson manifold (M, π) is referred to as canonical if π is of constant rank.

Proposition 4.1  For a canonical Nambu-Poisson manifold containing a smooth subbundle ImπTM, we define a canonical foliation structure Fπ,TFπ=Imπ on manifold M, and induce a symplectic structure with foliation n-form on Fπ

ωFπΩn(Fπ)=Γ(nTFπ),

where ωFπb(π(α)),π(β)=12(π(α),βπ(β),α),α,βΩn1(M).

In the (n−1, k)-Dirac structure, if ρ(E)=prTME has a constant rank, then E is called canonical Dirac manifold. We can get the following theorem.

Theorem 4.1  There is an one-to-one correspondence between the canonical (n−1, n−2)-Dirac structure on manifold M and foliation structure Fπ in closed n-form ω on M.

Proof The corresponding (n−1, n−2)-Dirac structure on (Fπ,ω) is

E(Fπ,ω):={X+α:XTFπ,α|TFπ=iXω},

iun2iu1(X1+iX1ω,X2+iX2ω)+=12(iun2iu1iX1iX2ω+iun2iu1iX2iX1ω)=0.

There is a closed non-degenerate foliation n-form to the foliation structure Fπ shown above [25], so the one-to-one correspondence [3] between Nambu-Poisson structure and multisymplectic structure can be proved. □

There is (Tn1Φ)(Gr(π))=Gr(dΦ(π)) for Nambu-Poisson structure (given a multivariate vector field π, its graph is noted as E=Gr(π)Tn1M). If π is a Nambu-Poisson structure, and Rω(Gr(π)) transverses at TM, then Rω(Gr(π))=Gr(πω) induces a new Nambu-Poisson structure πω.

Lemma 4.1  Assume π is a Nambu-Poisson structure on M, and ωΩcln(M) is in closed n-form, then Gr(πω) transverses at TM if and only if

id+ωbπ:n1TMn1TM

is invertible, where the Nambu-Poisson structure πω defined by Gr(π)ω=Gr(πω) satisfies

(πω)=π(id+ωbπ)1.

Proof From the definition

Gr(πω)={π(μ)+μ+iπ(μ)ω|μn1TM}.

Gr(πω) transverses at TM if and only if the projections on n1TM are isomorphic, that is if and only if for any vn1TM, there exists

v=μ+iπ(μ)ω(id+ωbπ)μ.

Hence it is proved with (πω)(υ)=π(μ).□

We call πω the gauge transformation of π induced by closed n-form ω.

Lemma 4.2  The Nambu-Poisson structures πω and π define the same n-symplectic leaf, whose n-form is related to the pullback of ω.

Proof It follows through Lemma 4.1 that the rank of (πω) equals that of πω. Let mM, the form on TFπ(m)=Im(πm) defined by πm is σ.

If w1,w2TFπ(m),wiπm(μi),μin1TM, then

σ(w1),w2=πm(μ1),μ2=μ1,w2.

Assume σω is n-form defined by πω

σω(w1),w2=v1,w2,

here (πω)v1=w1, then

v1=(id+ωbπ)μ1=μ1+iw1ω.

Hence σ(w1),w2=v1,w2=σ(w1),w2=ω(w1),w2.

From Lemma 4.2, n-symplectic foliation structure can be described with the method of (n−1,n−2)-Dirac geometry as follows.

Theorem 4.2  Assume πtXn(M) is a single parameter variety of Nambu-Poisson structure, the corresponding gauge transformation is

πt=(π0)ωt,

where ωtΩn(M) is in n-form with closed variety, ω0=0.

Let

dωtdt=dαt,αtΩn1(M).

Define vector field Xt=πt(αt). Let the flow of Xt be Φt, then

(dtΦ)πt=π0.

Proof From the definition Xt+αtΓ(Gr(πt))=Γ(Rωt(Gr(π0))), assume βt=αti(Xt)ωt, then Xt+βtRωt(Gr(πt))=Γ(Gr(π0)). It is the section of (n−1,n−2)-Dirac structure Gr(π0), so the flow generated by (dβt,Xt) maintains the graph of Gr(π0). It can be computed with Theorem 3.3 that

(dtΦ)dβt=(dtΦ)(dαtLXtωt)=(dtΦ)(dωtdt+LXtωt)=ddt((dtΦ)ωt).

The flow is ((dtΦ)ωt,Φt). Then

Gr(π0)=((dtΦ)ωt,Φt).Gr(π0)=R(dtΦ)ωtTn1Φt(Gr(π0))=Tn1ΦtRωt(Gr(π0))=Gr((dtΦ)πt).

We get π0=(dtΦ)πt.

Definition 4.2 [27] For the n-vector field πN on N and n-vector field πM on M, if πMϕ(p)=(dpϕ)πNp, we say πM and πN are ϕ correlated, and ϕ is Nambu-Poisson morphism, where (dpϕ):nTpNnTϕ(p)M.

Theorem 4.3  Let (N,πN),(M,πM) be a Nambu-Poisson manifold, ϕ is a Nambu-Poisson morphism if and only if Tn1ϕ:(Tn1N,Gr(πN))(Tn1M,Gr(πM)) is (n−1,n−2)-Dirac morphism.

Proof  ϕ is a Nambu-Poisson mapping if and only if

πN(ϕμ1),ϕμ2=πM(μ1),μ2

holds for any μ1,μ2n1TM. This is equivalent to

dϕ(πN(ϕμ))=πM(μ).

For any μn1TM, there is

πN(ϕμ)+ϕμϕπM(μ)+μ.

Which means that for any xGr(πM)ϕ(n), there exists the only yGr(πN)n,yϕx

The previous section proves that (n−1,n−2)-Dirac structure ϕ!Gr(π)Tn1N can be pulled back with transversal conditions of ϕ, but the pulled back π is not a Nambu-Poisson structure. The necessary and sufficient conditions for pulled back π to be Nambu-Poisson structure are presented below.

Theorem 4.4  (M,π) is a Nambu-Poisson manifold, mapping ϕ:NM transverses at π if and only if ϕ is an immersion mapping, satisfying

TM|N=TNπ(annn1(TN)),annn1(TN)={δn1TN|X,δ=0},

here ϕ!Gr(π)Tn1N has defined a Nambu-Poisson structure.

Proof It can be seen from the above theorems that ϕ!Gr(π) defines a Nambu-Poisson structure if and only if it transverses at TN,TN(ϕ!Gr(π))=TM|N. But ϕ!Gr(π)TN contains special element yTn1N,yϕ0. Let y=w+ν,wTN, νn1TM, which indicates that ν=0,wker(dϕ). Hence ker(dϕ) = 0

Assume ϕ is an immersion mapping, wTNTn1N, we get

wϕπ(μ)+μGr(π)(dϕ)(w)=π(μ),μker(ϕ)=annn1(TN).

The condition is ϕ!Gr(π)TN=0π(annn1(TN))TN=0.

5 Integrability of pullback (n1, 0)-Dirac structure

The definition of higher order Dirac structure given in this paper [8, Definition 4.13] is a special case. From the one-to-one correspondence between higher order Dirac structure and Lie algebroid given in [8], it can be seen that the higher order Dirac structure defined in this paper also has corresponding Lie algebroid, which similarly can be integrated into (n−1)-presymplectic groupoid. Based on [7], this paper studies the integrability of the pulled high-order Dirac structure. Through the (n−1, 0)-Dirac structure pullback under transversal conditions given in Section 3, this section investigates the integrability of the pulled back (n−1, 0)-Dirac structure.

To study the integrability of (n−1, 0)-Dirac structure, we first look at the (n−1, 0)-presymplectic groupoid. Firstly the definition of (n−1, 0)-symplectic groupoid is introduced. Given a Lie groupoid g for any (n−1, 0)-Dirac structure E on manifold (n−1, 0)-, the n-form ω on g is multiplicable, if

mω=p1ω+p2ω,

where pi:g2g,i=1,2 is natural projection. Then (n−1)-symplectic groupoid turns out a Lie groupoid gM combining a multiplicable n-symplectic form ω.

Let A=ker(ds)|M correspond to Lie algebroid on g, the anchor mapping is ρ=dt|A:ATM, then any closed multiplicable form ωΩn(g) defines vector bundle mapping

μω:An1TM,μω(a)=(iaω)|TM,δω:ATn1M,δω(a)=(ρ(a),μω(a)),

where there is one-to-one correspondence iurω=t(μω(u)),uΓ(A) between multiplicable n-form on g and IM n-form μ on A.

Definition 5.1 [1] One (n−1)-presymplectic groupoid is a Lie groupoid gM combining a closed multiplicable n-form ω, satisfying

(1) ker(ω)gker(ds)gker(dt)g={0};

(2) dgt(ker(ω)gker(ds)g)=(ker(ω)TM)t(g).

Theorem 5.1 [5]  Assume (g,ω) is an any source simply connected (n−1)-presymplectic groupoid on M, where ω corresponds to infinitesimal μ. Then there exists the only (n−1, 0)-Dirac structure ETn1M, where E is isomorphic to the Lie algebroid corresponding to Lie groupoid.

Theorem 5.2 [1]  Let E be an (n−1, 0)-Dirac structure isomorphic to integrable Lie algebroid, then there exists the only source simply connected (n−1, 0)-presymplectic groupoid (g,ω) which can be integrated by E.

In this way, (n−1, 0)-Dirac structure can define a Lie algebroid. Let the dimension of manifold N be n, there exists Nambu-Poisson structure πN=x1xn on Tn1N, where the graph of πN corresponds to the (n−1, 0)-Dirac structure on N, then the Lie algebroid defined by the (n−1, 0)-Dirac structure is integrable. If it is integrated into (n−1)-presymplectic groupoid, the integrability of (n−1)-Dirac structure can be converted into a study of the integrability of the Lie algebroid defined by itself.

Assume (g,ω) is the (n−1)-presymplectic groupoid on M, there exists anti-Lie algebroid isomorphism in the corresponding Lie algebroid isomorphism δω:AE

δωop:AopEop,a(ρop(a),μωop(a)),

where μωop:Aopn1TM. If AE, then AopEop, conduct mapping (X,α)(X,α), and normally we assume it is identical.

The kernel of (n−1, 0)-Dirac structure E is defined as ker(E):=ETMTM.

Lemma 5.1  There exists one Nambu-Poisson structure if and only if ker(E)=0 on E.

Proof Let the kernel of (n−1, 0)-Dirac structure E be 0, then E=(πα,α)TM=0π=0, so that there exists one Nambu-Poisson structure π on E. On the contrary, let π(α1)=X,π(α2)=X, then π(α1α2)=0 contains α1=α2,ker(E)=0. □

There is a closed n-form on ω, where ker(E)=ker(ω).

E2|ϕ(x)={(dϕ(X),β)|(X,ϕβ)E1|x},

and when ker(dϕ)ker(E1)={0}, mapping ϕ:M1M2 is a push-forward (n−1, 0)-Dirac morphism, hence ϕ is called strong (n−1, 0)-Dirac mapping.

Definition 5.2 Assume (M1,E1),(M2,E2) is an (n−1, 0)-Dirac manifold, if xM1,

E2|ϕ(x)={(dϕ(X),β)|(X,ϕβ)E1|x},

the following presents the relationship between the kernel of (n−1, 0)-Dirac structure and integrable (n−1, 0)-presymplectic form.

Lemma 5.2  Let source simply connected (n−1)-presymplectic groupoid (g,ω) be the integral of Lie algebroid on (n−1, 0)-Dirac structure E. Then,

(1) the mapping (t,s):gM×Mopis a strong Dirac map (there exists anti-higher order Dirac structure on Mop);

(2) we can obtain that under identity mapping δω:AE,δωop:AopEop

ker(ω)|g={ar+inv(b)laker(E)|t(g),bker(E)|s(g),inv:EEop}.

Proof Assume gg,s(g)=x,t(g)=y. For aA|y,bAop|x, according to the definition of Li algebroid anchor and dt(ar)|g=ρ(a)|y,ds(bl)|g=ρop(b)|x and multiplicability of multisymplectic structure [8], it can be derived that

iarω=t(μω(a)),iblω=s(μωop(b)).

Considering mapping AE,AopEop, let AE,AopEop, for ZTgg, let Z=(ar+bl)|g satisfy (dt,ds)(Z)=(X,Y). Then

iZω=iarω+iblω=tα+sβ=(t,s)(α,β),

which proves that (t,s):gM×Mop is a Dirac mapping, and according to the Definition 5.2, it can be seen that the mapping is a strong (n−1, 0)-Dirac mapping.

If mapping ϕ is an (n−1, 0)-Dirac mapping, then ker(E2)|ϕ(x)=dϕ(ker(E1)|x), and the condition of strong (n−1, 0)-Dirac mapping is equivalent to dϕ:ker(E1)|xker(E2)|ϕ(x), so it is isomorphic. The strong (n−1, 0)-Dirac mapping ϕ:(M1,E1)(M2,E2) can induce the function of Lie algebroid on manifold M1

ϕ:E2TM1,(Y,β)|ϕ(x)X,

where X is well-determined by Y=dϕ(X). This mapping is restricted to ϕker(E2)ker(E1) on vector bundle. Hence the Lie algebroid function of E×Eop can be induced on groupoid g.

tE×sEopTg,(a,b)ar+bl,

so as to define an isomorphic mapping ker(E)|t(g)×ker(Eop)|s(g)ker(ω)|g, so the proposition is proved.□

From Section 3, it can be known that (n−1, 0)-Dirac structure can be pulled back into (n−1,0)-Dirac structure under transversal condition. The following mainly studies the integrability of pullback (n−1,0)-Dirac structure.

The function of Lie group H on Nambu-Poisson manifold M is written as q:H×MM,(h,m)hm. If the diffeomorphism qh:MM of any hH is a Nambu-Poisson morphism, then q is called the Nambu-Poisson function. On the n-symplectic manifold (M, ω), if q is the Nambu-Poisson function, then equation qhω=ω is established. We study from the principle H-bundle.

Definition 5.3 [19] The Nambu-Poisson function of Lie group H on is written as q. If q is free, appropriate and reducible, then a principal H-bundle can be defined

π:MM/H.

Theorem 5.3 [19]  A Lie group function is free, appropriate and reducible on Nambu-Poisson manifold M. Then there exists the Nambu-Poisson structure (redn1TM,πred) on M/H, and the quotient mapping Π is Nambu-Poisson morphism.

Assume H is a Lie group, its corresponding Lie algebra is h, consider the Lie algebroid function on manifold M on principal H-bundle π:MM/H, the corresponding anchor mapping is ρM:h×MTM, where Im(ρM)=ker(dπ:TMT(M/H)). Assume F is any (n−1, 0)-Dirac structure on M/H, which is still an (n−1, 0)-Dirac structure after pullback from mapping Π. The definition is as follows:

E=π!F={(X,πβ)F}Tn1M.

Let FE=(π!F). Then there is one-to-one correspondence between the (n−1, 0)-Dirac structure on M/H and H-invariant (n−1, 0)-Dirac structure Im(ρM)ker(E) on M, and under the correspondence F is the push forward of E:

F=π!E:={(dil(X),α)(X,πα)E}Tn1(M/H),

corresponding to ker(F)=dπ(ker(E)),ker(E)=(dπ)1(ker(F)). In particular, F is the graph of Nambu-Poisson structure on M/H if and only if the higher order Dirac structure E=(π!F) is H-invariant on M, and ker(E)=Im(ρM),

Assume (E,ψ) is the H-Lie algebroid on M, morphism ψ:h×ME,(u,x)(uM|x,0), g is a Lie groupoid integrated by E on manifold M.

Assume Ψ:HMg is a Lie groupoid morphism obtained by Lie algebroid morphism ψ integration.

The (n−1, 0)-Dirac structure on M/H can be defined as an H-Lie algebroid (π!F,ψ), so the integrability of (π!F,ψ) can be studied with that of (n−1, 0)-Dirac structure on M/H.

Definition 5.4 Assume g is a Lie groupoid on M. It can be obtained from (Lie algebroid) integral E that there exists the Lie algebroid morphismψ:h×ME that can be integrated into a Lie groupoid morphism Ψ:HMg. Then the Lie algebroid Tπ(M/H) defined by Nambu-Poisson structure can be integrated into a Lie groupoid g¯=g/(H×H).

Definition 5.5 Let F be a higher order Dirac structure on M/H. If the Lie algebroid morphism can be integrated into a Lie groupoid morphism , and the H×H function ω on g remains H×H invariant, then the presymplectic groupoid (g,ω) integrated by the pullback higher order Dirac structure is called H-compatible.

Define a quotient Lie groupoid g¯=g/(H×H) and a quotient mapping p:gg¯, on manifold M/H, which is also a submerged sum groupoid morphism.

Theorem 5.4  Assume F is an (n−1, 0)-Dirac structure on M/H, and E=(π!F) is the pullback (n−1, 0)-Dirac structure on M. If the H-compatible (n−1)-presymplectic groupoid (g,ω) is obtained through E integration, there exists the only pre(n−1)-symplectic structure ω¯ such that pω¯=ω on quotient Lie groupoid g¯=g/(H×H). The unique source simply connected (n−1)-presymplectic groupoid (g¯,ω¯) can be obtained through F integration.

Proof Firstly we deduce the function of H×H on g through that of H×H on g,

ρg:(h×h)×gTg,ρg(u,v)|g=(ψ(u,t(g)))r+(inv(ψ(v,s(g))))l.

It can be known that from Im(ρM)ker(E) and Lemma 5.2, ρg(h×h)ker(ω) and the H×H function of ω remains the same, then ω has a H×H basis, and there exists ω=pω¯ corresponding to the only n-form ω¯ on g¯. Since π:gg¯ is a groupoid morphism, ω is multiplicable, so that we get dim(g/(H×H))=2dim(M/H). Finally, let A¯ is the Lie algebroid of ω¯, the corresponding mapping is δω¯:A¯Tn1(M/H). δω is injective, so ker(δω¯)=0 can be deduced from ker(δω)=0. In fact, assume α¯ker(δω¯), we can get ρ¯(α¯)=dπ(ρ(a))=0,πμω¯(α¯)=0, where for any α, there is α¯=dπ(a). Then in ρ(a)=ρ(ψ(u)), transform α into a=aψ(u), such that dp(a)=α¯, μ(a)=0, ρ(a)=0, hence a=0, α¯=0. Therefore, (g¯,ω¯) obtained through (M/H,F) integration is a presymplectic groupoid. □

6 Conclusions

On the basis of previous researches, this paper studies with a higher order perspective. Based on the automorphism groups and automorphism Lie algebra on higher order Courant algebroid, the gauge changes of single parameter variety of the Nambu-Poisson structure have been obtained. We have also established the relationship between the (n−1, n−2)-Dirac structure and the Nambu-Poisson structure under smooth morphism, and proved the integrability of the pullback (n−1, 0)-Dirac structure under quotient mapping.

References

[1]

AlbaN M. On higher Poisson and higher Dirac structures. Ph D Thesis, Rio de Janeiro: Institute Nacional de Matematica Pura e Aplicada, 2015

[2]

Álvarez D. Integrability of quotients in Poisson and Dirac geometry. Pacific J Math 2021; 311(1): 1–32

[3]

Bi Y H. Sheng Y H. On higher analogues of Courant algebroids. Sci China Math 2011; 54(3): 437447

[4]

Bi Y H. Sheng Y H. Dirac structures for higher analogues of Courant algebroids. Int J Geom Methods Mod Phys 2015; 12(1): 1550010

[5]

Bi Y H, Vitagliano L, Zhang T. Higher omni-Lie algebroids. J Lie Theory 2019; 29(3): 881–899

[6]

BursztynHCabreraAIglesias-PonteD. Multisymplectic geometry and Lie groupoids. In: Geometry, Mechanics, and Dynamics, Fields Inst Commun, Vol 73. New York: Springer, 2015, 57–73

[7]

BursztynHIglesias-PonteDLuJ H. Dirac geometry and integration of Poisson homogeneous spaces. 2021, arXiv: 1905.11453

[8]

Bursztyn H, Martinez Alba N, Rubio R. On higher Dirac structures. Int Math Res Not IMRN 2019; 2019(5): 1503–1542

[9]

Cantrijn F, Ibort A, de Leon M. On the geometry of multisymplectic manifolds. J Austral Math Soc Ser A 1999; 66(3): 303–330

[10]

Courant T J. Dirac manifolds. Trans Amer Math Soc 1990; 319(2): 631–661

[11]

CourantT JWeinsteinA. Beyond Poisson structures. In: Troisième Théorème de Lie, Travaux en Cours, Vol 27. Paris: Hermann, 1988, 39–49 (in French)

[12]

Gualtieri M. Generalized complex geometry. Ann of Math (2) 2011; 174(1): 75–123

[13]

Hitchin N. Generalized Calabi-Yau manifolds. Q J Math 2003; 54(3): 281–308

[14]

Ibáñez R, de León M, Lopez B, Marrero J C, Padrón E. Duality and modular class of a Nambu-Poisson structure. J Phys A 2001; 34(17): 3623–3650

[15]

Ibáñez R, de León M, Marrero J C, Martín de Diego D. Dynamics of generalized Poisson and Nambu-Poisson brackets. J Math Phys 1997; 38(5): 2332–2344

[16]

Lang H L, Sheng Y H. Linearization of the higher analogue of Courant algebroids. J Geom Meeh 2020; 12(4): 585–606

[17]

Liu Z J, Weinstein A, Xu P. Manin triples for Lie bialgebroids. J Differential Geom 1997; 45(3): 547–574

[18]

Meinrenken E. Poisson geometry from a Dirac perspective. Lett Math Phys 2018; 10(3): 447–498

[19]

Nakanishi N. On Nambu-Poisson manifolds. Rev Math Phys 1998; 10(4): 499–510

[20]

Nambu Y. Generalized Hamiltonian dynamics. Phys Rev D (3) 1973; 7: 2405–2412

[21]

RoytenbergD. Courant algebroids, derived brackets and even symplectic supermanifolds. Ph D Thesis, Berkeley: University of California, 1999

[22]

Sheng Y H, Zhu C C. Poisson geometry and Lie n-algebras. Sci Sin Math 2017; 47: 1717–1734

[23]

Ševera P, Weinstein A. Poisson geometry with a 3-form background. Progr Theoret Phys Suppl 2001; 2001(144): 145–154

[24]

Takhtajan L. On foundation of the generalized Nambu mechanics. Comm Math Phys 1994; 160(2): 295–315

[25]

Vaisman I. A survey on Nambu-Poisson brackets. Acta Math Univ Comenian (N S) 1999; 68(2): 213–241

[26]

Vallejo J A. Nambu-Poisson manifolds and associated n-ary Lie algebroids. J Phys A 2001; 34(13): 2867–2881

[27]

Zambon M. L-algebras and higher analogues of Dirac structures and Courant algebroids. J Symplectic Geom 2012; 10(4): 563–599

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