Constraints from conformal symmetry on the three point scalar correlator in inflation

  • Nilay KunduEmail author
  • Ashish Shukla
  • Sandip P. Trivedi
Open Access
Regular Article - Theoretical Physics


Using symmetry considerations, we derive Ward identities which relate the three point function of scalar perturbations produced during inflation to the scalar four point function, in a particular limit. The derivation assumes approximate conformal invariance, and the conditions for the slow roll approximation, but is otherwise model independent. The Ward identities allow us to deduce that the three point function must be suppressed in general, being of the same order of magnitude as in the slow roll model. They also fix the three point function in terms of the four point function, upto one constant which we argue is generically suppressed. Our approach is based on analyzing the wave function of the universe, and the Ward identities arise by imposing the requirements of spatial and time reparametrization invariance on it.


Conformal and W Symmetry Conformal Field Models in String Theory 


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) 2015

Authors and Affiliations

  • Nilay Kundu
    • 1
    Email author
  • Ashish Shukla
    • 2
  • Sandip P. Trivedi
    • 2
  1. 1.Harish-Chandra Research InstituteAllahabadIndia
  2. 2.Department of Theoretical PhysicsTata Institute of Fundamental ResearchMumbaiIndia

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