Wave function of the Universe and CMB fluctuations

@article{Alwis2019WaveFO,
  title={Wave function of the Universe and CMB fluctuations},
  author={Senarath P. de Alwis},
  journal={Physical Review D},
  year={2019}
}
  • S. D. Alwis
  • Published 30 November 2018
  • Physics
  • Physical Review D
The Hartle-Hawking and Tunneling (Vilenkin) wave functions are treated in the Hamiltonian formalism. We find that the leading (i.e. quadratic) terms in the fluctuations around a maximally symmetric background, are indeed Gaussian (rather than inverse Gaussian), for both types of wave function, when properly interpreted. However the suppression of non-Gaussianities and hence the recovery of the Bunch-Davies state is not transparent. 
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