Abstract

We study the cohomology of the massless BRST complex of the Type IIB pure spinor superstring in flat space. In particular, we find that the cohomology at the ghost number three is nontrivial and transforms in the same representation of the supersymmetry algebra as the solutions of the linearized classical supergravity equations. Modulo some finite dimensional spaces, the ghost number three cohomology is the same as the ghost number two cohomology. We also comment on the difference between the naive and semi-relative cohomology, and the role of b-ghost.

Highlights

  • Vertex operators are one of the central objects in string theory

  • If the BRST cohomology at the ghost number three is zero any infinitesimal deformation can be continued to a finite deformation, at least as a power series in ε

  • [8] In [8] we concentrated on the perturbation theory around AdS5 × S5, while in the present paper we work in flat space

Read more

Summary

Introduction

Vertex operators are one of the central objects in string theory. They represent cohomology classes of the BRST operator. It is well known that the physically relevant cohomology problem is the so-called semirelative cohomology [2], which is QBRST acting on the vertex operators V satisfying the following condition: This condition was built-in into the computations of [1]. To defeat the ghost number three cohomology is more difficult It is dangerous as a potential obstacle for continuing an infinitesimal solution to a finite solution (i.e. obstructed deformations of the flat spacetime). We do not have such a proof in the pure spinor formalism It follows from the consistency of [6] that there is no obstacle in extending the infinitesimal deformation to higher orders. It would be good to have a transparent proof of this fact using the language of BRST cohomology and vertex operators This would probably require the use of the composite b-ghost

Plan of the paper
Classical sigma-model and its deformations
From integrated vertex to unintegrated vertex
Ghost number three vertices as obstacles to deformations
Conclusion
Ghost number three cohomology is nonzero
Cohomology at ghost number four and higher is zero
Argument for vanishing of the obstruction based on symmetry
Super-Maxwell BRST complex
Definition of the doubled complex
Cohomology of classical electrodynamics
Cohomology of R10 with values in solutions of Maxwell equations
Cohomology of R10 with values in solutions of Dirac equations
Zeroth cohomology of the tensor product of two classical electrodynamics
First cohomology of the tensor product of two classical electrodynamics
Dirac–Dirac sector
This means that the only nontrivial components
Bi-Maxwell equations
Double field strength is the obstacle to triviality
Dirac–Maxwell sector
Maxwell–Dirac sector
Ghost number one
Ghost number two
Comment on nonphysical states
Ghost number three
The bispinor m
Ghost number four
Action of the supersymmetry on the ghost number three vertices
Left supersymmetry on the Maxwell–Dirac sector
Left supersymmetry on the Dirac–Dirac sector

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.