Initial state of matter fields and trans-Planckian physics: Can CMB observations disentangle the two?

  title={Initial state of matter fields and trans-Planckian physics: Can CMB observations disentangle the two?},
  author={L.Sriramkumar and T.Padmanabhan},
The standard, scale-invariant, inflationary perturbation spectrum will be modified if the effects of trans-Planckian physics are incorporated into the dynamics of the matter field in a phenomenological manner, say, by the modification of the dispersion relation. The spectrum also changes if we retain the standard dynamics but modify the initial quantum state of the matter field. We show that, given any spectrum of perturbations, it is possible to choose a class of initial quantum states which can… 

Does Planck actually “see” the Bunch-Davies state?

To what extent can the Planck satellite observations be interpreted as confirmation of the quantum part of the inflationary paradigm? Has it “seen” the Bunch-Davies state? We compare and contrast the

Could PBHs and secondary GWs have originated from squeezed initial states?

Recently, the production of primordial black holes (PBHs) and secondary gravitational waves (GWs) due to enhanced scalar power on small scales have garnered considerable attention in the literature.




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