Asymmetrically twisted strings

TL;DR

This paper introduces a new class of asymmetrically twisted strings characterized by an integer parameter, revealing unique mass spectra and interactions, and proposing a novel four-point amplitude structure with a generalized dressing factor.

Contribution

It presents the concept of asymmetrically twisted strings, exploring their spectrum, interactions, and a conjectured four-point amplitude generalization inspired by Kawai-Lewellen-Tye relations.

Findings

Massless resonances plus open string spectrum at level N

Conjectured asymmetrical KLT relation at four points

Four-point amplitudes with generalized Virasoro-Shapiro factor

Abstract

In this letter a new class of twisted strings is presented, with an asymmetry between the holomorphic and antiholomorphic sectors parametrized by an integer $N$. Their physical content is given by the massless resonances of the closed string plus the mass-level $N$ spectrum of the open string. The appeal of this model is the singling out of the (higher spin) massive levels of string theory together with their self/gauge/gravity interactions. Motivated by the original tree level Kawai-Lewellen-Tye relation for closed strings, its asymmetrically twisted version at four points is conjectured and shown to naturally interpolate with conventional and twisted strings. The resulting four-point amplitudes have a generalized Virasoro-Shapiro dressing factor.