Abstract

The contribution from even spin structures to the genus-two amplitude for five massless external NS states in Type II and Heterotic superstrings is evaluated from first principles in the RNS formulation. Using chiral splitting with the help of loop momenta this problem reduces to the evaluation of the corresponding chiral amplitude, which is carried out using the same techniques that were used for the genus-two amplitude with four external NS states. The results agree with the parity-even NS components of a construction using chiral splitting and pure spinors given in earlier companion papers [29] and [33].

Highlights

  • The study of perturbative scattering amplitudes in string theory dates back to the founding of the subject and continues to provide deep insights into the dynamics of string theory today

  • The contribution from even spin structures to the genus-two amplitude for five massless external NS states in Type II and Heterotic superstrings is evaluated from first principles in the RNS formulation

  • Using chiral splitting with the help of loop momenta this problem reduces to the evaluation of the corresponding chiral amplitude, which is carried out using the same techniques that were used for the genus-two amplitude with four external NS states

Read more

Summary

Introduction

The study of perturbative scattering amplitudes in string theory dates back to the founding of the subject and continues to provide deep insights into the dynamics of string theory today. We present a variety of new simplified spin structure sums of multiple products of Szegö kernels and streamline the manipulations of the Beltrami differentials in the moduli-space integrand These new techniques will be, no doubt, crucial for subsequent investigations of multiparticle and higher-genus amplitudes. Our results may be of use in relating the correlators of the ambi-twistor string [42, 43] to those of the conventional superstring [44, 45] This relation was already used in the proposal of [46] for the genus-three four-point amplitude as an uplift of the low-energy limit of the amplitude derived in [28] to higher orders in α. The final expression for the amplitude is, remarkably simple and we shall begin by a summary in the sequel of this introduction

Summary of results
Comparison with lower genus
Structure of the five-point NS string amplitude
The super period matrix
Parametrization of super moduli space adapted to projection
The chiral measure
Bottom component of the measure
The chiral amplitude
Correlators of chiral vertex operators
Contribution from disconnected correlators
Contribution from connected correlators
The connected parts Y1 and Y2
Structure of the spin summands
Preview figure for the simplification process
Wick contractions of fermions
Closed loops of Szegö kernels
Closed loops of Szegö kernels with a fermion stress tensor
Open chains of Szegö kernels
Spin structure sums
Auxiliary holomorphic forms
Sums involving the fermion stress tensor
Evaluating J10
Evaluating J11 and J12
Fundamental simplifications and cancellations
Cancellation of F4
Cancellation of F1ψψ
The function Λ
Assembling the chiral amplitude
Combining the contributions of F1xx and F2x
Part three: one bosonic vertex contracted with a prefactor
Calculation of F1n
The contribution from F3
Assembling and simplifying the chiral amplitude
Re-expressing Lμν
Contraction with Bμν
7.11.1 Alternative presentation
Uniqueness of the kinematic factor
Uniqueness of the odd parity chiral amplitude
Conclusions and future directions
Modular transformations on θ-functions and characteristics
Calculation of J6
Calculation of J9
Consistency checks for J6 to J9
Evaluating L1
Evaluating L2
Findings
Consistency checks for L1 and L2

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.