On this page:
1 Families with the structure of vector bundle
1.1 A subset of with additional structure
1.2 Continuation problem
1.3 A vector bundle over
2 Application to RNS formalism
2.1 Base family
2.2 Subspaces
2.3 Are there solutions to continuation problem?
2.4 Split family

Familty of Lagrangian submanifolds

1 Families with the structure of vector bundle

1.1 A subset of with additional structure

Consider a subset invariant under the group of diffeomorphisms . Suppose that:
  1. Every Lagrangian submanifold comes with a subspace of functions on it:

    (in our application this subspace will be finite-dimensional)

  2. There is an action of on this subspace, more precisely for each we are given a linear map :

    such that

1.2 Continuation problem

Question: we want to continue every function from from the Lagrangian submanifold to the full BV phase space:

so that the continuation satisfies the following two properties:
  1. For every fixed , the extended functions are all in involution w.r.to the odd Poisson bracket on :

    (but for two different and in , the functions extended from are not required to be in involution from the functions extended from )

  2. The extension commutes with the action of diffeomorphisms:

    (26)

is this possible?

Suppose that the answer is “yes”. Then we can enlarge to a larger subset of which has a structure of a vector bundle over , as we will now describe.

1.3 A vector bundle over

We define as the total space of the following vector bundle over : the fiber over is the orbit of under the Hamiltonian vector fields generated by all the Hamiltonians from .

Instead of the elements of being in involution with each other, we could have required that the space is closed under the Poisson bracket. But then would not be a vector bundle, just some nonlinear bundle.

Eq. (26) guarantees that:

is diffeomorphism-invariant

2 Application to RNS formalism

2.1 Base family

Let be a set of all split worldsheets, i.e. worldsheets with split superconformal structure:

It was shown in PerturbativeSuperstringTheoryRevisited that the antifields to tetrad have zero modes (see our notations). To follow the standard notations, we denote the leading component of .

2.2 Subspaces

In this case, we will choose as follows:

generated by the integrals:

with running over the representatives of the Dolbeault realization of .

2.3 Are there solutions to continuation problem?

We do not have an explicit solution of the continuation problem. Actually, we do not even have a proof that the solution exists.

2.4 Split family

But if the continuation problem has solution, then we can construct a split -dimensional cycle in the following way:
pick any - dimensional cycle in the moduli space of bosonic Riemann surfaces and restrict to this cycle

The requirement of diffeomorphism-invariance in the continuation problem was crucial for us, because it guarantees the action of the mapping class group on our cycle.