Asymmetrically twisted strings

Understand

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.