Fermionic zero-norm states and enlarged supersymmetries of Type II string

TL;DR

This paper investigates fermionic zero-norm states in type II string theory, revealing their role in supersymmetry and proposing the existence of enlarged symmetries at high energy, while discussing R-R charges.

Contribution

It identifies fermionic zero-norm states responsible for supersymmetry and proposes new enlarged symmetries from massive states, expanding understanding of string symmetries.

Findings

Massless and some massive zero-norm states generate supersymmetry.

Higher spinor-tensor zero-norm states imply enlarged boson-fermion symmetries.

Massive R-R zero-norm states suggest possible massive R-R charges.

Abstract

We calculate the NS-R fermionic zero-norm states of type II string spectrum. The massless and some possible massive zero-norm states are identified to be responsible for the space-time supersymmetry. The existence of other fermionic massive zero-norm states with higher spinor-tensor indices correspond to new enlarged boson-fermion symmetries of the theory at high energy. We also discuss the R-R charges and R-R zero-norm states and justify that perturbative string does not carry the massless R-R charges. However, the existence of some massive R-R zero-norm states make us speculate that string may carry some massive R-R charges.