Journal of High Energy Physics

, 2016:36 | Cite as

On the null origin of the ambitwistor string

  • Eduardo Casali
  • Piotr TourkineEmail author
Open Access
Regular Article - Theoretical Physics


In this paper we present the null string origin of the ambitwistor string. Classically, the null string is the tensionless limit of string theory, and so too is the ambitwistor string. Both have as constraint algebra the Galilean Conformal Algebra in two dimensions. But something interesting happens in the quantum theory since there is an ambiguity in quantizing the null string. We show that, given a particular choice of quantization scheme and a particular gauge, the null string coincides with the ambitwistor string both classically and quantum mechanically. We also show that the same holds for the spinning versions of the null string and ambitwistor string. With these results we clarify the relationship between the ambitwistor string, the null string, the usual string and the Hohm-Siegel-Zwiebach theory.


Conformal Field Theory Scattering Amplitudes Superstrings and Heterotic Strings 


Open Access

This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.


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Copyright information

© The Author(s) 2016

Authors and Affiliations

  1. 1.Mathematical InstituteUniversity of OxfordOxfordU.K.
  2. 2.Department of Applied Mathematics and Theoretical PhysicsCambridgeU.K.

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